It might be fraud, but I can envision this being very difficult to prove, not least because you only bring it up now that it is to your benefit to do so.
If it indeed was fraud, the documents may be void - but I would be highly sceptical that a court would nullify a mortgage that you had been benefiting from for two years without giving the lender some recourse against you. By signing and having the mortgage notarized subsequently, you may have acquiesced in or ratified the act, and may be complicit in the fraud.
I'm also curious how you suffered any damages by this. You've had the benefit of the mortgage for the last two years. Even if it was fraud, and you were not complicit, how have you been harmed?
You are correct, the notary's governing body should be notified. You may wish to contact them to explain the situation and give them a chance to explain to you why what they did might not be fraud, and give them a chance to self-report before you do.