well, it actually does not prove anything at all.
for instance, tskhinvali is also known as chreba within osetians…
georgia kingdom was stronger in military terms, georgians had better developed state and corresponding governmental structures. osetians were considered as savage people. there was a big deal of georgian chauvinism regarding these people.
georgian kingdom was actively assimilating abkhazians and osetians.
for instanse, even during soviet rule – abkhazian language was banned. everything had to be written in georgian language only. osetian and abkhazian schools were banned. education was allowed in georgian only.
interesting, that it was contradicting general soviet standards.
everywhere in ussr, national republics had two official languages – russian and local.
local language was legally enforced everywhere – official paperwork, street plates e.t.c..
everywhere, but georgia..