I will try to explain, Jesus commanded us to love even our enemies. These men, especially the "Judas" who gave you assurances that I am sure you knew at the time were nonsense have set themselves as your enemy, the enemy of truth, and the enemy of Christ Jesus. My point is you are frustrated by men who do not care about you and do not care that they are spouting lies everytime they go on the platform. You were concerned about doctrines that were based on lies. They do not care about your concerns, only devotion to the organization is important to them because your devotion to the organization secures their power over you. I was suggesting you tell them that you love them even though they are seeking to put you to death, in a figurative sense.
Just like the example of Stephen, even though he was literally put to death, he prayed to Jesus to forgive those who were killing him. Jesus himself made that same ultimate expression of love to those who put him to deah by appealing to his Father not to charge that sin against them.
I was suggesting you show love to them in a similar way. Forgive them and tell them you love them but do not submit yourself to their abuse and treacheary.
In my opinion, to write a letter of DA only gives them claim on authority that Jesus never bestowed upon them or any man. In the end they spin it the way they want to anyways.
You might try writing a letter to members of the the congregation explaining the situation but it is doubtful many will believe you. Some might listen and believe you but will not have the strength to stand up for truth like you have. If just one listens though, will it not be worth it?
A JC was convened for me and the only reason why I attended was I believed I could plant seeds of truth in some of their hearts. When it became abundantly clear to me and those who I had believed were honest were now showing themselves to be dishonest I left the meeting. I knew what they were going to ultimately do and felt sorry for them because the Bible is quite clear about what judgement is in store for these oppressive wolves.
The most clear and undisputable teaching of Christ was to love another. Jesus also said you would know his followers by the love they had for one another. In this regard you are heeding his command by separating yourself from these unloving and therefore Godless men.
All the Best and May Christ comfort you! I can empathize with what you are going through.