Even real AOTCs are not an indication of skill, Moose runs in WoD were proof of that. It was a mere 40k for a moose run and you got the added perk of flashing your AOTC (and legendary ring which the moose quest help you get) to get into heroic raids despite being 1/10H and that 1 being a carry.
AOTC is pointless on its own. If someone doesn't have 10/10 H but still has AOTC you should assume they bought their run or were carried.
Pugging is always going to be plagued with failures, you should assume every pug sucks until they prove themselves.