Akthi and Anundr duo boss fight invulnerability bug after boss overlap

Bug report ID: #3,341,259,761.

When in the boss room of a map, fighting the duo boss, the scorpion boss got stuck in the tail of the sandworm. This makes it invulnerable and stuck in place, and the game won't let you warp out of the boss fight, and the instance seems to persist across servers.

I wasn't paying attention to the exact conditions during the fight, but I suspect the sandworm dug its way through the scorpion and that's what lead to it getting stuck.