I'm thinking it was Orton, he's always been more outspoken than your typical WWE superstar. I remember a couple of years back in a non-kayfabe interview, where he spoke of his joy at "being on a different show to Triple H". To those unfamiliar with this kind of stuff, Orton was essentially suggesting that Triple H took priority when it came to the main event, and that by being on a different show, Orton and others had a chance to work without fear of Triple H taking their spot. It is of course, unsubstantiated, but some wrestlers (past and present) feel/felt that Triple H has held them back, despite the evidence that suggests otherwise (Triple H has put over numerous talent strongly, throughout his career).
Back to the original topic though, there is only a handful of people that could get away with directly challenging Vince McMahon in that way, they include:
I can't think of anyone else who A) is inclined to voice up, B) immune from demotion or any other consequences, and C) close enough to McMahon, where he will take what they say seriously and personally.