Completing PTI does not fall into any of the questions you mentioned above. After completion of PTI the State will Nolle Prose the case, therefore there is no conviction, w/h of adjudication or suspended sentence. However, they will find your arrest and you will probably be questioned further.
For it to be Theft he must have purchased something with the credit card and then refused to pay his credit card bill. He definitely needs to speak to an experienced Criminal Defense attorney as there will be defenses he can raise.
Any attorney who is allowed to practice in any US jurisdiction can file an FTCA claim, however if the case has to be filed in court, the attorney will have to be a member of the Pennsylvania Bar or one of its District Court Bars, or to file a Pro Hac Vice notice with a local attorney as co-counsel.