Blameless
Is it possible that gospel of the kingdom has been preached in all the world?
First off, we see that the whore of all the earth had dominion over all the earth, among all nations, kindreds, tongues, and people.
1 Nephi 14:11 And it came to pass that I looked and beheld the whore of all the earth, and she sat upon many waters; and she had dominion over all the earth, among all nations, kindreds, tongues, and people.
So we see that an earthly power had the comprehensive dominion over everything. Did the whore reach every tribe of the jungles? No. So "all nations, kindreds, tongues, and people" doesn't mean what is commonly understood.
Kings an governments are nothing in the face of the all powerful God. They are "as the blossoms of a thistle, which, when it is fully ripe, if the wind bloweth, it is driven forth upon the face of the land" (Mosiah 12:12). They are nothing. If they don't let the Christian message reach their people, God works with that. He created a nation on the promised land where he drew all nations, kindreds, tongues, and people which became a nation of immigrants.
2 Nephi 1
5. ....[W]e have obtained a land of promise, a land which is choice above all other lands; a land which the Lord God hath covenanted with me should be a land for the inheritance of my seed. Yea, the Lord hath covenanted this land unto me, and to my children forever, and also all those who should be led out of other countries by the hand of the Lord.
6. Wherefore, I, Lehi, prophesy according to the workings of the Spirit which is in me, that there shall none come into this land save they shall be brought by the hand of the Lord.
7. Wherefore, this land is consecrated unto him whom he shall bring. And if it so be that they shall serve him according to the commandments which he hath given, it shall be a land of liberty unto them;
We see here that people are brought here to the American continent where they are exposed to the commandments. They are all exposed to the Christian message. They see churches on every corner. They go to museums and see Gospel events painted and sculpted. They read the classics that all refer to Christian principles. They see the birth and death of Christ celebrated. If nothing else, the hear the name of Christ used as curses. They are all exposed to Jesus.
Again, are there Arab Christians? Chinese Christians? Christians from all nations, kindreds, tongues, and people? Yes, there are.
Lets say the Gospel is what Paul says it is.
1 Corinthians 15
1. MOREOVER, brethren, I declare unto you the gospel which I preached unto you, which also ye have received, and wherein ye stand;
2. By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain.
3. For I delivered unto you first of all that which I also received, how that Christ died for our sins according to the scriptures;
4. And that he was buried, and that he rose again the third day according to the scriptures:
5. And that he was seen...
This is well known to pagans, heathens, atheists and faithful.
Now, go to the streets of any nation, kindred, tongue, and people. Ask them:
Have you ever heard the song "Joy to the World?
What is Christmas all about?
What is Easter all about?
What are the Ten Commandments?
What is the meaning of the cross on yonder church?
Can you name one of the Ten commandments?
Can you tell me one teaching of Jesus?
Can you list a few characteristics of God?
Did you see the movie, "Passion of Christ"? "The Ten Commandments"?
How does one pray? What is prayer for?
Where do you go to learn God's teachings?
You will get answers that indicate that they have been exposed to the Gospel. I think a survey conducted like this anywhere will yield answers more or less accurate. Some will be ignorant and some intelligent. Some will believe and some will reject. But everyone, it will be discovered, has some knowledge of the Gospel.
All who have exposure to the Gospel will be held accountable.
Mosiah 3
20. And moreover, I say unto you, that the time shall come when the knowledge of a Savior shall spread throughout every nation, kindred, tongue, and people.
21. And behold, when that time cometh, none shall be found blameless before God, except it be little children, only through repentance and faith on the name of the Lord God Omnipotent.
22. And even at this time, when thou shalt have taught thy people the things which the Lord thy God hath commanded thee, even then are they found no more blameless in the sight of God, only according to the words which I have spoken unto thee.
Every word of the Book of Mormon, even single letter words, are important. Notice that the citation does not say “the knowledge of THE Savior shall spread”. it says “the knowledge of A Savior shall spread”. This indicates that what is spread may not be accurate or complete. But all will know about a Savior.
Nobody starts with a complete knowledge. We learn line upon line, precept upon precept. The first “line” may be viewing “The Last Supper” while visiting Milan (who is not familiar with that work?). The first precept might be seeing a gorgeous sunset over the ocean and the spirit whispering “a wonderful God did that”. However He chooses,
Alma 5:33 Behold, he sendeth an invitation unto all men, for the arms of mercy are extended towards them, and he saith: Repent, and I will receive you.
You cite often the parable of the Sower. Well, you see that the seeds are spread universally. The parable tells of no ground that didn’t receive seeds.
I believe that all nations, kindreds, tongues, and people have been reached.
Breathing
How does this work? I think John Wesley hit the nail on the head. He taught that God manifests Himself onto all by what he calls a breath. This voice of the Good Shepherd
…necessarily implies the continual inspiration of God's Holy Spirit; God's breathing into the soul, and the soul's breathing back what it first receives from God; a continual action of God upon the soul, and a re-action of the soul upon God; an unceasing presence of God, the loving, pardoning God, manifested to the heart, and perceived by faith; and an unceasing return of love, praise, and prayer, offering up all the thoughts of our hearts, all the words of our tongues, all the works of our hands, all our body, soul, and spirit, to be a holy sacrifice, acceptable unto God in Christ Jesus.
[This will] infer the absolute necessity of this re-action of the soul, (whatever it be called,) in order to the continuance of the divine life therein. For it plainly appears, God does not continue to act upon the soul, unless the soul re-acts upon God. He prevents us indeed with the blessings of his goodness. He first loves us, and manifests himself unto us. While we are yet afar off, he calls us to himself, and shines upon our hearts. But if we do not then love him who first loved us; if we will not hearken to his voice; if we turn our eye away from him, and will not attend to the light which he pours upon us; his Spirit will not always strive: He will gradually withdraw, and leave us to the darkness of our own hearts. He will not continue to breathe into our soul, unless our soul breathes toward him again; unless our love, and prayer, and thanksgiving return to him, a sacrifice wherewith he is well pleased.
God can “breath” on us by putting a desire in our hearts to believe (Alma 32:27). He can frighten you at the funeral of a friend. He can inspire you to do a good thing so that you experience the joy of well-doing.
Moroni 7:13 But behold, that which is of God inviteth and enticeth to do good continually; wherefore, every thing which inviteth and enticeth to do good, and to love God, and to serve him, is inspired of God.
We start down the path that leads to God as we respond to that invitation. Wesley referred to these initial whispers as “preventing grace”, that is, grace that comes before saving grace that we will eventually come to as we respond to the voice of the Good Shepherd.
Not Blameless
Mosiah 3
20. And moreover, I say unto you, that the time shall come when the knowledge of a Savior shall spread throughout every nation, kindred, tongue, and people.
21. And behold, when that time cometh, none shall be found blameless before God, except it be little children, only through repentance and faith on the name of the Lord God Omnipotent.
This can only be true if He, indeed, has manifested and invited all to come unto him.