What exactly do you plan to do? The term "first amendment auditing" could mean a lot of different things, after all. If what you plan to would violate any law then that will almost certainly violate your probation since a standard condition of every probation order I've seen requires the probationer not to violate any laws.
For that you need to read your probation order. Some orders say that if you have any contact with law enforcement you must disclose to the officer your identity and that you are on probation. If you have that requirement and don't do it, that itself can be a violation of your probation.
That wrongful arrest by itself should not violate your probation. But if the conduct that lead up to the arrest was a crime or otherwise violated your probation that would be a problem. The specific details of what occurred are going to matter.

