Unable to Progress/Extract to next Deep Archemedia mission until specific players died?

[Hinus]

My partner and I were matchmaked with two randoms on public matchmaking. While progressing from the second mission to the third of this week's Archimedia, we got stuck.

One of the randoms died the mission before / first mission (survival) and we extracted instead of killing the angel since they'd be brought back anyways, after second mission (alchemy) we could not progress to the final mission despite the fact all of us were standing on the extraction platform & was showing 3/4 players waiting the whole time. One of them said they were bugged (the one where you can't shoot or melee attack?) and then they died, then the three of us couldn't extract as it was then stuck on 2/3, and then the other random let themself die, and only when it was me and my partner did the mission finally finish and extract the team to move on to the next mission with all of us alive.

No one missed out on any rewards, but it was just very weird and I'm not sure what caused the bug?

[Imvakihn]

Partner in question, corroborating this experience