I dunno why but if Wesker lives it'll be a miracle, since the blast of the RPG would definitely kill anyone, and is strong enough to even destroy tanks. Plus, two rockets are fired, which means it's even more deadlier.
But meh, it's the miracle of videogames, you don't really know what to suspect since they can easily go through reality. So, Wesker still has a possible chance to live, Uroboros might be really protecting him, or he could've survived the blast, but only time will tell.
But Wesker is probably one of the best characters out there and if they kill him off like that I'm sure a lot of fans would be disappointed... Including me.