You've never actually seen the Khajiit from Daggerfall, have you? They have tails.
That's a good point. Ohmes-raht do have tails, now, Ohmes do not have tails, as far as I know, that's the main difference between Ohmes and Ohmes-raht.
As to whether they're Khajiit, I'd say the fact that other forms of Khajiit can give birth to them is pretty solid evidence, in general, dogs don't give birth to cats, dogs give birth to other dogs, it works like this here too. The child of a Khajiit is probably going to be a Khajiit, just as you can expect a Dunmer's child to be a Dunmer, generally speaking. They may look pretty different from other types of Khajiit, but that's how it works. What type of Khajiit is born is determined by the cycles of the moons, so a Khajiit that looks like a house-cat could potentially be the mother of an Ohmes, it doesn't make much sense if you go by real life genetics, but the Elder Scrolls isn't real life.
Bethesda should just go back to the Morrowind concept art: http://www.imperial-..._mw_khajiit.gif
That Khajiit just looks like a cheesy rubber monster from a low budget science-fiction show to me, and doesn't even look very cat like.
Since we have the "sub races" of humans (Bretons, Imperials, Redguards, Nords) in the games we should at least have one or two extra for the Khajiit.
I agree completely there, but what can you do? A fantasy setting that has more than one or two races that aren't just humans with pointy ears, funny skin colors or some sort of verticle deficiency is probably too original for the sort of players that developers seem to think make up the majority of the gaming community to comprehend.