Got broken treasure maps and SotD bug at local co-op too. However it's a little bit different. I don't even see any SotD at all. Treasure maps in inventory have been at 0 Gold, new can't get picked up, nothing appear. Dropped the maps some days ago and changed areas serveral times since I read it can be "too many maps owned" but this doesn't work. Checking game files also doesn't work. A fix for this would be good, maybe an Option to turn on/off SotD and treasure maps so you could somehow reactivate the spawning. Such option would be also good for server owners as some maybe don't want SotD at all. This bug exists at least since 2019 it seems. I found some topics about it when searching but not any working solution and it's really game breaking.