They may very well have fired this person because they were trans, however if the grounds for termination are valid this person can claim discrimination all they want. Just because they are trans doesn’t mean they get a pass on being negligent. I retired recently, 40 years in the workforce, 30 years with the DoD. Over time I saw plenty of people let go for something other than why they really fired.
Yes,that’s certainly possible...but if that’s the real reason they *cannot* admit it in court.If they do he’ll probably win...and get a million (or more).