For me, the game keeps crashing at the Frozen Maw meta now right in the moment when the now corrupted Svanir Shaman would die. I tried it with two different characters on two different servers and had this crash both times exactly when the boss died. When trying to log in with the character afterwards on the server that had the boss, the game will keep crashing over and over. However, I could log in with other characters or with the same character on a different server. I also got the daily bonus chest for the first character that I tried doing the Maw with, but I never got the normal chest on the ground. After a few minutes, probably when that ground chest has despawned, I am able to log in with the character and server again without crashing.
I’m not 100% sure, but I think the Toxic Spore Cleanser achievement has advanced for the Svanir Shaman despite the crashes.
Same here, got the crash when the boss died, could relog after chest had despawned.