DB/SAI: Misc Fixes from IT

By @dr-j and @untaught
Fixes #11081 fixes #11080 fixes #11082
Core/Quest: Remove assertion

Remove assertion about Quest ExclusiveGroup since they are triggered even when adding valid quests to npcs. Fixes #8336 .
How to reproduce steps:
- .gm off
- add quest 11335 in creature_queststarter
- .reload creature_queststarter
- get in range of that creature
- .gm on
- assertion triggered