Official correcting improper Time out call

[port23]

Middle school Team A is driving to basket on fast break at end of second quarter.

Coach A yells to players on bench about proper defensive technique on the last play.

Official interprets the instructions Coach A is yelling as a Time Out call by Coach A. Coach A did not use the words "time" or "out" or anything that rhymes with them.

When Coach A explains that he did not want the time out, especially to stop a fastbreak with 3 seconds remaining, the official charges Team A with a Full time out and says his call is uncorrectable.

Is there an inadvertent whistle rule that would deal with this situation?