if the referee has deemed that as Abusive/Insulting or whatever term you wish to use at the time, then he can justify a RC.
Things always look different real time, remember, he can feel, hear, smell the environment/tempo that he is in, we are merely watching a clip and going , oft that's harsh. We always like to look at something and go, oh, that's not what I would have done, or, I like to think I would have handled it differently, however, until it is "us" out there, in the heat of THAT moment, faced with THAT situation, we truly don't know. For my 1% that's its worth, I like to think I would have thought, hey, was that on purpose, really, surely not....but, if I did, after weighing it up in my mind, replaying it etc..then a 2nd yellow would have been my call