Free throw violations

[Mr.C]

Hi,

First post on this site. I had a situation in a middle school boys game using nfhs rules. a)A1 is at the free throw shooting the double bonus----second free throw. B2 steps in the lane before the release and my partner holds out the delayed violation signal. A1 does not draw iron and I whistle a violation. How would that be handled? I thought both violations would be enforced, leading to an AP throw in, but that is not what we did. We gave a substitute free throw------only other thing I could think of is that my partner thought the early movement disconcerted the shooter? We did not have the chance to discuss it after the game. Thanks