In transmitters ,some transmitters use a different frequency multiplication scheme. The crystal oscillator may be require a different loading of the crystal. The capacitve loading of the crystal will also dictate a different crystal.
So much for the "A CRYSTAL is A CRYSTAL" stuff that has been spouted here recently huh ? And so much for the new Amateur Extra Class examination since one of those folks was an Extra Class amateur.
No evil conspiracy just an engineering call. Still the right crystal is the way to go.