HR fired me over the phone on Wednesday for job abandonment because I left work early Saturday with permission from the manager on duty. This was coincidentally the day after I submitted a retaliation complaint to the company's third-party investigators. I received an email from them today asking if I can come into an onsite meeting to discuss the results of the investigation tomorrow. My inside scoop tells me the company's attorney determined that I shouldn't have been terminated and that HR are going to claim that they hadn't fired me on that phone call. The thing is I recorded that call. These guys have made the majority of my time there a nightmare and id like to return the favor. Do I have anything to work with here? Any Ideas for the best move to make this a pain in the ass for them?