Strange situation

[illini]

rule 5.3.3, case book page 17, situation C after the first referee whistles and signals for the serve, the second referee sounds the whistle for a substitution.
Ruling: incorrect procedure, the ball is dead, substitution is denied, and a new whistle and signal for serve is given.

In my defense on this rule, I am substituting the word sub for time out, in either case the 2nd referee blew a whistle. By rule, you recognize the whistle, replay, sub and or time out is denied!

I do agree with MCbear, that no card is warranted in this situation. However, disagree with the fact the statement it is a free pass of allowing the subs. It is an inadverant whistle by R2, replay any corrective actions/timeouts are denied, by rule.