She was terminated for cause.  Perhaps it was poor public relations for the company, but that does not make it 'wrongful.'  

The pastor perhaps made a poor public relations choice too, but that has little or nothing to do with the waitress losing her job.   If the pastor somehow violated the terms of her employment contract, she would rightly be subject to being fired by her congregation, but there is no evidence applying to that in either direction, and it really has nothing to do with the issure of the waitress being fired.