Take a look at this video of the 2004 NCAA Men's Division I Basketball Championship Game between UConn and Georgia Tech.
Georgia Tech made a 3-pointer with 11.7 seconds left. Then a UConn player grabbed the ball to inbound it and the referee started the 5 second countdown. The UConn player looked around to try to inbound the ball, and after 3 seconds, he threw the ball to another UConn player who had run out of bounds. After 2 more seconds, the second UConn player finally inbounded the ball. Based on the referee's arm motions, it appeared the second UConn player inbounded the ball just after the 5 second count, which should be a violation, but none was called.
Is switching inbounders after the referee has started the 5-second count allowed only in college, or is it allowed in the NBA as well? Does the referee start over with the 5-second count after there is a switch of inbounders?