Still Raul in FO2 was a nothing character. Why out off all the people in FO2 that have bigger parts would the Devs bring him back? I am not saying it can't be him but why?
It would be too much of a coincidence. A mechanic, a long-lived ghoul, the name of another mechanic in the same general area of the world...
And a follower voiced by a person of sheer awesome. And thus it would be very interesting to hear what he did in the time gap.
At any rate, we will know once we hear Raul talk. Raul will just talk like Raul does, as Raul mentions the name Raul quite often. ^_^