According to Victor the aliens tend not to last too long on Earth. They are prone to infections, especially respiratory ones, but he doesn't know if the alien in the video died. He did say that it was not interviewed any more, but he suggested it could have been retired from the interview process.
He was asked why the aliens didn't seem bothered about dying. His reply was that the aliens saw their physical bodies as mere vessels and that their consciousness continued after death. They also saw our obsession with technology and rushing to advance it as peculiar to us.
Apparently a deal had been struck wherein they swapped some of their technology with us in exchange for genetic material (for an unknown purpose). Unfortunately the scientists at Area 51 had great difficulties with the ET technology and the interviews facilitated a way for answers to be sought.
Victor made it clear, though, that the aliens could be uncooperative in imparting information, but he thought that this may be down to their thoughts having to be interpreted by telepaths.
He also said that there was a high attrition rate among the scientists, as their egos were often bruised at their inability to fathom out the alien technology.
It's a fascinating documentary and worth watching, even if it is a hoax... or not :)