Stealth Mobs

I've been hearing that there are some issues with stealthed mobs as I've been leveling up, but until today, I've never had a problem with them. The issue was when trying to target a mob that stealthed and neutral to both factions. I ran all around Dustwallow trying to target (using a macro) these mobs, and all I managed to target were some toads. The mobs in question were the Theramore Infiltrator for http://db.vanillagaming.org/?quest=1201
Has the Nost team recognized the untargetable stealth mobs as an issue, or is there some way to find and kill these things?
Has the Nost team recognized the untargetable stealth mobs as an issue, or is there some way to find and kill these things?