I’m quite perturbed to note that my posting of this topic continues in a tradition that’s gone back multiple years.
On this forum alone, multiple posts exist since 2019 discussing how “The Lost Legion” bounty is bugged, in that even after the entire legion + unique demons are defeated, the chest remains in its “cursed” state and cannot be opened. This means that Act V bounties for the entire run cannot be completed, which is quite frustrating when grinding out mats.
I personally encountered this one week ago on EU realms, and then again tonight on NA realms.
However, what I find particularly worrying is a reddit post from 7 years ago detailing the exact same bug: https://www.reddit.com/r/diablo3/comments/2igls1/hideout_of_the_lost_legion_bounty_bug/
If no effort is going to be put into fixing this bug, at least retire the bounty so it doesn’t continue causing problems?