Scrimmage kick caught by K. Touchback

[Cottondale]

K81 is running downfield to cover a scrimmage kick. At the 2 yard line, K81 catches the scrimmage kick, has possession, and his momentum carries him (and the ball) into the end zone. No R player was in the area, no KCI. Is this a touchback? I know when I say it would be the rule on Sundays someone is going to say that's a different set of rules...I know that, but what are the rules everyone in the crowd (and some on the sideline) know? Everything I've read says the ball is dead when the kick is possessed...at the 2. The momentum of the receiver wouldn't apply. K cannot advance it, even the 2 yards needed for a touchback. I have not had this happen to me yet, but I'd like an opinion for when it does.

[maven]

You've answered your own question. The kick ends when it is possessed. K cannot advance a scrimmage kick untouched by R and caught or recovered beyond the NZ. The ball is dead when K catches or recovers a kick beyond the NZ.

So, the ball is dead when possessed by K on the R2. You're not likely to see this play, however, because the players will think they must down the ball outside the EZ like they see on TV.

[Cottondale]

And that is exactly what I was thinking.  I can't find a rule or case book play that tells me otherwise.  The momentum exception does not apply because this is K catching the kick.  Since I can't find something to tell me otherwise, I thought I'd put it on here to see if someone knew of a rule that I am missing.

[Ralph Damren]

A thing to keep in mind on this or plays where R is attempting to catch the kick is was possession gained or was the ball juggled as the player entered the endzone? If the player didn't have full possession of the ball before the ball broke the EZ plane then by rule you have a touchback. If it was K that juggled the ball into the endzone, you techinally had first touching where he first made contact with the ball - an option you should keep to yourself - don't put the kids in position to make a poor decision.