I saw the interview, recorded it. So you're angry that he didn't merely mention that Elmo is a Muppet OR the name Jim Henson? Big deal! We know Elmo's "a Muppet," Kevin knows Elmo's "a Muppet," frickin' Matt Lauer knows that Elmo's "a Muppet," whether Disney/Sesame owns the name or not. Geez, I doubt Kermit mentions he's a Muppet every time he's interviewed.
As for the interview itself, it was a nice and short--just five minutes long--and he talked a little about his book, how he wanted to be in children's television, his daughter, and how Elmo came to be. He actually mentioned Richard Hunt, Kermit Love, and "Frank" during the interview, so I think he very well knows what organization he comes from.
As for Kevin himself, he could not have been any less "rude or unthoughtful," even throwing Elmo's voice in here and there. It's rare nowadays when you actually get to see a Muppet performer being interviewed on TV, and I enjoyed it.
Didn't hear the word "Muppet?" Well, buy his book, I'm sure it's gotta be in there somewhere.