A friend and I were going to casually farm the rare bucket boss in mythic Tol Dagor (only spawns in no keystone). We downed the second boss so when we enter the trash will be gone and we spawn near the bucket location.
All goes well for the first person to enter, but the second gets placed at the entrance in a different, totally new instance with all trash and bosses up. Either one of us can enter solo and be put at the lockout position, but if the other tries to enter the reset instance happens. Also if someone without a lockout tries to join.
Is this meant to happen?