Catcher's balk/interference??

[Young_Ump]

Little League Juniors game. I'm behind the plate. Runner on first base takes off for second, pitcher throws the slowest pitch ever and the batter has no intention of swinging at it. The catcher comes all the way out on top of home plate to catch the ball and throw it down to second. First thing I did was call the pitch a ball. Then I thought about the so-called catcher's balk rule. But since we give warnings for balks anyways, I didn't call anything other than a ball. I know OBR only has that as a balk + catcher's interference, but only with R3 stealing home... should I have called a catcher's balk or catcher's interference? And can you have a catcher's balk with a runner stealing 2nd or 3rd?

[The Man in Blue]

That was the case play I was thinking of.  Thank you @Senor Azul!