Alright, my first question about the Camoran Dynasty, is it still around? Was the Camoran Usurper the last member of the Camoran Dynasty or did Kaltos Camoran reclaim his throne? And was Mankar Camoran actually the son of the Haymon Camoran? I believe that the anwser is still unknown, but I might be mistaken.

Don't know about the first question, but i can go into the question about Mankar. Technically speaking it's unknown, there was a son named Mankar but since his mother was a Bosmer he would've been a Bosmer as well, since that's how genetics work for at least the playable races in the games. However, considering the Mankar in Oblivion managed to modify his own ancestry so he was never really born in the first place, severing all ties with his own mother, it could be he even changed his race to Altmer to further sever the biological ties. So it could very well be he was formerly Haymon's son before the biological ties were severed.

At the time of Skyrim? No definitive proof, but very likely. They were very much around at the time of Oblivion. Although she never appears in-game, you impersonate a "Celia Camoran" during the final quest to steal an Elder Scroll. They are likely a noble family of much importance in the empire, given that one of their number was given exclusive access to the Imperial Library.