I know nothing about the situation, but it’s not like that stopped me from responding before!
It’s a shame that those mods aren’t doing a better job at protecting an author from abuse (where they can reasonably do so). Assuming the mods aren’t being malicious in this, I can think of some reasons. 1) the horde replied to the summons, so you’re now one voice vs many on the matter, and they chose to believe the majority. 2) The mods don’t like your pairing either (or one of them has become part of the horde). 3) Way overloaded, and, well you’re one vs many. Trouble with trolls, it’s like weeds in a garden, let one stay, and you’re soon overran by them; chasing good authors away isn’t a good long term strategy.
I second JayDee’s opinion, be the adult. If AO3 isn’t a good fit for you, well, AFF’s archives are open