NCAA Rules Interp help

[NSABlue]

This happened to my daughters team and was looking for help with the rules interpretation.
Situation: R1 @ 2nd base and one out. Batter hits a sharp ground ball which is fielded cleanly by the 1st baseman. The Batter-runner takes only 3-4 steps toward first and stops. This forces the first baseman to either throw to 1st for the out or come towards the plate and tag the runner. She chooses the latter and R1 advances to third. When the 1st baseman comes to tag the B-R she tags her up near the shoulder. As she applies the high tag (No malicious tag, just a little high), the B-R leans back towards home plate. The B-R never moved her feet. The plate umpire calls the B-R out and leaves R1 at third. The defensive coach appeals to the Plate umpire who then confers with his partner. After the conference, the umpires return R1 to 2nd base. Is "leaning back" considered
moving back toward home plate in NCAA? I understand the rule but I disagree with this interpretation. Any NCAA blues out there that can shed a little light on this one?

[Skahtboi]

If the umpire was calling the BR out due to rule 12:3:k, the runner retreating toward home to avoid or delay a tag, then the ball should have been dead immediately, and the rummers returned to the base they occupied at the time of the pitch. So...if that was the ruling of the umpires, then the eventual return of R1 to second was the correct ruling.

Now, to answer your question about the play itself, it is possible that the umpires ruled this an attempt to avoid or delay a tag, but the rule clearly states "steps back." Not having been there, and going solely on the information you provide, I probably would not have had the out unless something else occurred, such as a step back or the actual tag itself. However, this is a judgement call on the part of the umpire, so.....