After multiple attempts, I ended up abandoning the run.
However I zipped the diagnostics and save files just before doing so: Endless Dungeon.zip
There was no CrashDump file unfortunately and I did not save the Player.log files immediately after the crash, so they likely are not relevant.
"I was the host of a 3-player co-op game, and we all crashed pretty much simultaneously (crash to desktop, no error message or anything) while playing in Astral Harbor second section. This is bad enough but it gets worse.
I am unable to continue the run, it seems to load but ends abruptly, as shown in this short clip:
https://youtu.be/xEwNZwivyI4