I dont know if bathroom caulk will work, not for long anyway. Ring pressure might go through it, push it out. What factory used was a very strong molded plastic. The part is reproduced. Link to the vendor was in a recent thread.
I too pulled the ring off with vise grips on the tang. I knocked the ring back on with a big line wrench and a hammer. The tang of ring in the wrench jaw opening. First C shaped something I saw worked. Good luck with it.