If they can't drop a simple $200 charge, that should not have been charged in the first place, to keep their own customers happy, I don't think it is a company worth my time.
Hate to say it but they don't have to keep you happy any longer, because you are no longer a customer for T-mobile. I bet they put you into a contract when a rate plan was changed. The only way you can ever find out your contract date is to call customer service. They don't allow that information to be seen any other way. It sounds like you just got the runaround in the store, because they definitely don't give credits for ETF fees and customer service doesn't do it either, unless it's because of death and even then they want proof of that.