Um, I'm sure you know you're already in the wrong for having an affair while still married, and even you admit how you can see why your ex-husband has every right to be mad at you. I'd say that what he said between him and an MS is privileged information, between them. It's their opinion. It does show you however how the MS and others feel, so consider it special insight, a window into their minds.
Now, knowing all this, what are you going to do? Do you really think bringing private, privileged correspondence to your Body of Elders who are automatically on the male MS's side, going to hurt THEM, or YOU? It's not going to do a damn thing except cause them to think you are a complete shit-stirrer. You'll NEVER be reinstated!!! Is the MS a douchebag? Most likely. Is the male-run Elder body going to do a damn thing about it based upon your tattling to them about it? Absolutely NOT, and YOU will be made out to be the bad guy. It's called, "Victim Shaming", and these freakin' clowns have it down to a science.
My advice? Either a.) Get the out of that freakin' cult NOW, or b.) if you want to retain family ties, smile, come to all meetings, play the "reinstatement game", then fade out afterwards while retaining family ties. Then, send that douchebag of an MS a "get f*cked" card, anonymously.
The choice is yours.