Monsters spawned in areas you can't get to

I'm running a t15 map on an Oasis map node in the Atlas. As the title suggests there are monsters that spawned in an area that players can't get to. The map is "juiced" up and therefore has extra mob density that it wouldn't normally have. Not sure if that's what lead to this bug or what. It is keeping me from completely the map. Not the end of the world by any means but hopefully a quick fix can come of this. I have a photo of the monsters and where they are and of the map itself to show what I'm talking about if you guys need it.