I'm not sure about this is a bug but I know for sure that something is wrong. On Trabia server in The Black Shroud sites for the quest both npc giving ash reward got stuck.
Also I'm disappointed because I called a GM to notify and look for solution to complete quest but I just got answered with the premade message telling you to post on forum and bla bla... meanwhile time passed, I lost anima travelling among sites and after 3 hours my LS friend discovered you could actually get reward by standing where npc is stuck and talking to him just after bomb reached the goal on the other side of the map...
was it a really hard answer to give even if GM aren't meant for in game bugs?
anyway the problem is that people who are actually pushing the bomb cannot return in time to the stuck npc to get reward