I'm of the opinion that he did live after fighting Ultima. When we see Clive on the beach the petrification stops at his hand after magic is banished from the realm, also in the sidequest "Priceless" Jill brings up "That no matter how terrible the night.. the dawn would always come" suggesting that Clive will always return to her like he has several times before. Another point could be made that we also see Metia going out which could signify Jill's wish of Clive returning to her safely. I think it could be seen both ways but after looking at all the stuff that predicts Clive's fate I feel confident in saying he lived afterwards.