I'm no lip reader and it was obvious even to me he was saying timeout.
You can't turn "timeout" into "they're clapping", this isn't some cheap Chinese movie voice-over. I know roughly how many movements with a mouth it takes to make one or the other. It was obvious. He clearly repeated "timeout". Go ahead, test it yourself. Look in the mirror and say "clapping" then say "timeout", you'll notice it doesn't look the same.
That and he was doing the timeout signal repeatedly, that or he has some serious physical disability rendering him unable to make another gesture.
Edit: If I was a ref I'd ignore every timeout call Kirby makes from here on out, "Oh sorry I thought you said something about clapping".