Players on the floor after 2Q, different in 3Q

[Rooster]

The varsity officials after my game had to deal with the home head coach who complained that the players at the end of the second quarter were different than the players who started the third quarter. According to HC, they did not check in before the 15 second warning buzzer starting the third quarter. He confirmed with the official scorer that no one had checked prior to that buzzer.

My question, How can we enforce 3-3-1a if no one keeps track of the players leaving after the second quarter? Are we expected to keep track?