Nesan, if your wife's PR application is rejected she will still be able to come to Canada as a visitor visa-free, since she is French. The border officials probably suspect she will not leave Canada when she comes because she is coming to visit her husband, so she should always have proof she is going back to France - such as a return ticket, proof of a job in France, money in a French bank account, etc. She may not ever need to show this, but she should have it just in case she is asked for it.
Most likely her PR application will be accepted, so don't worry about that. Very few are rejected from Western European countries.
And the next time she is hassled by a government official for not speaking English, she should insist on service in French. It is the law that government service be available in both official languages, and the taxpayers pay a lot of money for unnecessary bilingual staff in places where it is not really necessary, so it should be available when we or other people need it!