I've read the entire thread. that person did call you a guy and a dude, and their response is a pretty sad face-saving excuse.
The way you have constructed this post reads to me like a vague call to action detailing the crimes of a person and group of persons. This may not be your intent, but at least one person interpreted it that way. You may wish to reflect on that in your future posts.
Your feelings are real and valid, but your actions based on them only seem to be making it worse for yourself.
How so? They were insulted in a place that was supposed to be a safe space for trans people, so they went to another space that is supportive of trans people for support.
I'm cis, but it would probably suck to have a space online that is supposed to be for a vulnerable group and the admins and mods spend more time catering to and protecting those that want to harass and abuse that group than they do to the group itself. Someone who feels attacked or alone because of that behaviour shouldn't feel afraid to reach out in other places where they do feel safe to talk.
Hey victim, I know this person hurt you, but don't you think it's better to let people hurt you and let that hurt roll off your shoulders instead of confronting them and expecting abusive behavior to have consequences?