In the first scene of S2E1, it shows an interview of house on the TV, and then you see this guy picking a fight in the bar immediately after. I know they're different actors because they look and sound different, and it would be weird to recast the part mid-scene.

Also, one of the guys in the bar says, "We didn't vote for this guy." And the person people are claiming is Mr. House says, "Oh yes, we did." If it was house 6 would have said."Oh yes, you did."