need serious help in my community

Hello. I'm a mod in r/witch_cult and recently we been having issues in it

After reaching 12K members the growth of the community fell horribly for no reason at all even though it's very alive and active. From 50K+ visitors a week to barely 9K that with the fact that it no longer appears in people's for you page

Another issue we been having is mass reporting. A headmod of another sub have been found to be mass reporting our sub Reddit which resulted in it getting a violation notice from Reddit and our head mod getting banned constantly (he appeals and it gets accepted but it takes around a day and he have been banned by mass reporting 4 times so far) we got physical evidence about the guy self admitting that he targets the community and it's headmod and i saw posts from months ago getting 4+ reports each

Any help?