seeing as this is related to their changing off old zones you should try report it as ingame bug/placement.

also op problem isnt gona be solved with sneak/invis if the high level mobs link to said low level pop mob, guess they could add some confrontation to the pop but best bet is to just move ??? to apropriat level area.

This should have been done allready when the zone was reconfigured for low + high level mob's, also any af quest spots should get same treatment and be relocated so one can do them without being 99.