Is that a Chiss with sunglasses?
For instance, notable Jedi often live well beyond their lifespans in holocrons, records, legend etc. so what about the chiss Jedi people play?
The fact that we can play as Chiss Jedi doesn't mean that there were actually canon Chiss Jedi in that period (saying that players can be Chiss is like saying that a Chiss has killed the Jedi class enemies; in other words that the canon Hero of Tython could be Chiss, which is highly unlikely in my opinion).
Anyway, I don't see a problem with some Jedi being Chiss (non-notable and not in great numbers): because of the war, many Jedi were to die prematurely and the updating of the archives probably wasn't the most important matter (except for the case of Master Gnost Dural's records, which information was direcly related to the War and to the Empire), especially since the archives themselves were probably disrupted, if not destroyed completely, with the Sacking of Coruscant.