If you removed some quest from quest_list you should remove 'object' folder, which contains ~ here: /usr/home/game/share/locale/germany/quest
1. Remove quest from quest_list
2. Remove 'object' folder
3. Compile your quests (make.sh)
Do it with shutdowned server or it may lead to unfavorable consequences.
I hope I've understood your post and problem correctly. With best regards.