Thoughts on the Prophet Never Leading Astray vs Free Agency

In the Joseph Smith Translation of Mark 9: 46 it says:
And if thine eye which seeth for thee, him that is appointed to watch over thee to show thee light, become a transgressor and offend thee, pluck him out.
That inspired verse negates the argument that it is impossible for the Prophet to lead us astray.
The last time I checked, our Father in Heaven considers "Free Agency" so important that it caused a war in the heavens, and continues today. Yet, the vast majority of members believe that God would restrict the agency of leaders, to make sure they didn't lead people astray? Wouldn't that violate the very foundation of God's laws? If the claim is examined, how is it that the Church was wicked enough to crucify Jesus Christ? Because, the prophets then, would be cared for, beginning at Moses. He didn't want the Church to go astray then. There are so many other examples that provide proof that is a false belief.
There are many scriptures that indicate there is to be an apostasy in the very last days. Remember there are many verses that talk about a "Remnant." That means most of the church won't be there anymore. Also, what is meant by the "daughter of Zion?" For, is she not under condemnation, a portion of the Church, which has to have the chains loosed from her neck?
Also, recall there are two Churches spoken of, which were righteous, in the latter day prophecies. One is the Church of Jesus Christ/Church of Latter Day Saints, and the other is the Church of the Firstborn. Have you ever pondered and studied the differences in those? I invite you to see! For in Doctrine and Covenants 76, we find that the Church of the Firstborn is the one we want to belong to, in order to dwell with God:
50 And again we bear record—for we saw and heard, and this is the testimony of the gospel of Christ concerning them who shall come forth in the resurrection of the just—
51 They are they who received the testimony of Jesus, and believed on his name and were baptized after the manner of his burial, being buried in the water in his name, and this according to the commandment which he has given—
52 That by keeping the commandments they might be washed and cleansed from all their sins, and receive the Holy Spirit by the laying on of the hands of him who is ordained and sealed unto this power;
53 And who overcome by faith, and are sealed by the Holy Spirit of promise, which the Father sheds forth upon all those who are just and true.
54 They are they who are the church of the Firstborn.
55 They are they into whose hands the Father has given all things—
56 They are they who are priests and kings, who have received of his fulness, and of his glory;
57 And are priests of the Most High, after the order of Melchizedek, which was after the order of Enoch, which was after the order of the Only Begotten Son.
58 Wherefore, as it is written, they are gods, even the sons of God—
59 Wherefore, all things are theirs, whether life or death, or things present, or things to come, all are theirs and they are Christ’s, and Christ is God’s.
There are many other verses that teach about the Church of the Firstborn, including in the Old Testament.
Finally, I implore you to study the words of Isaiah. We all need to know what he prophesied. Even from the very beginning, we see the direct application of the word of God to our Israel, our Latter Day Church. Read the whole of Chapter One, then read it again. All of it is a condemnation of the Church and the leaders. Just a sample:
21 ¶ How is the faithful city become an harlot! it was full of judgment; righteousness lodged in it; but now murderers.
22 Thy silver is become dross, thy wine mixed with water:
23 Thy princes are rebellious, and companions of thieves: every one loveth gifts, and followeth after rewards: they judge not the fatherless, neither doth the cause of the widow come unto them.
24 Therefore saith the Lord, the Lord of hosts, the mighty One of Israel, Ah, I will ease me of mine adversaries, and avenge me of mine enemies:
25 ¶ And I will turn my hand upon thee, and purely purge away thy dross, and take away all thy tin:
26 And I will restore thy judges as at the first, and thy counsellors as at the beginning: afterward thou shalt be called, The city of righteousness, the faithful city.
27 Zion shall be redeemed with judgment, and her converts with righteousness.
28 ¶ And the destruction of the transgressors and of the sinners shall be together, and they that forsake the Lord shall be consumed.
29 For they shall be ashamed of the oaks which ye have desired, and ye shall be confounded for the gardens that ye have chosen.
30 For ye shall be as an oak whose leaf fadeth, and as a garden that hath no water.
31 And the strong shall be as tow, and the maker of it as a spark, and they shall both burn together, and none shall quench them.
I know the majority of members will say, Isaiah was only speaking of the Israelites in his day. These verses do not apply to our time. If that is true, why did the Lord, Jesus Christ, counsel the Nephites in 3rd Nephi, to study the words of Isaiah? Why was it important to them, or us, to know what happened to ancient Israel? Do you think there is no reason behind it God speaking of it, and having Isaiah write extensively about it? That is foolishness. It is a type and shadow. Just as things played out in Isaiah's day, they would play out again in our day. Isaiah was shown that. That is why he wrote what he did. That is why Jesus, and many others, quoted Isaiah so much.
So, I echo the Savior's counsel, "Great are the words of Isaiah!" I implore you to read and understand his messages, and apply them to your life today. I find it helps my understanding by using IsaiahExplained.com.