Fired and filing with MCHR

I was fired from a library after 16 years or work there. Two year prior to being fired I reported my supervisor to the HR for making disparaging comments about my country, language and performance ( I have all the documents to HR by date and time) even my disability. After this he was demoted and I was as to say "persecuted"... I was send to EAP to correct my behavior and then I was fired as not having performed well and not providing good customer service.
I saved emails of customers praising my work and other documents.

I filed with MCHR. What do you think chances are for me to win against this institution? I want an apology other than compensation. Should I file with a law firm better? Is this a better chance to win?

Best regards,
Anila