This has not been made official by Summit, however Newmoonmovie.org has an exclusive here guys! I don't know how they did it, but they have managed to track down one of the other guys in the Wolf pack photos and he is none other than Tyson Houseman. His agency website has a headshot of him in his profile that exactly matches the shot taken of him with Taylor and the other guys! It also lists him as having a supporting part in New Moon!!
Obviously, none of us know for sure but I think NewMoonMovie have pretty much hit the nail on the head with this one!!!
In their original article, they also go on to say that they are pretty defiinate about Alex Meraz, which makes two of us!!