Purple Plate Room in Thunderhead Peaks not dropping next plate properly.

For some reason the Veteran Graveling Ghost Eater is not dropping the plate properly. For the past 3 days I've spent 20 minutes chain killing this thing to get the plate to drop, while I see 20+ players walk in and get theirs while I'm still there killing the vet time after time. There has to be something wrong, it seems like the last person who enters the room gets loot privilege or something similar to that happening. By the time I finally get my plate I usually only have a few minutes left on my "Light of Deldrimor" buff which prevents me from finding many chests, and rarely able to make the hidden one in the last room. Please look into this problem. Thank you.

Topic is covered in detail,merged by mod buts no insight from Anet offered.https://en-forum.guildwars2.com/discussion/65538/graveling-in-catacombs-violet-room-doesnt-drop-any-plate-merged/p1