Exact same issue on Xbox version. Quite annoying.

Restarted the game since I got sick of waiting. A bit of a pity since I already spent 8 hours collecting stuff when I got stuck the first time.

Only followed the main story line this time to get to the prodigal-prince as soon as possible (didn’t even raid the island on the way). This time it did go through and I finished the mission. Straight after I decided to see if the previous side quests that were glitchy before still were. First up the couple at a like that are looking for something: before I wasn’t able to talk to them and now it went through (didn't finish it yet). Next up the old dude in the cave: found him before but couldn’t speak with him, now I could. Killed him; claimed the mystery. Last but not least the dude that wants to fight an animal: before he died when I took a wolf to him, he died, that’s it. Kinda weird. This I think could have caused the initial bug, since it was the first glitch I encountered when the game froze. This time he died and a story started, and I could claim the mystery, so all seems to be working now.

The walkaround of restarting has worked so far. I play on Xbox btw.

Exact same issue on Xbox version. Quite annoying.