Hemorrhaging can be due to hemorrhoids. There was no bruising.
I doubt that he would have had a work related credit card. He would probably file vouchers.
DiBiagio, the US Attorney, was not a good boss, IMO. He could still fire JPL, and that would cause hiring problems alone. Especially with the Stash House case, Luna could be facing ethics problems. If he took the polygraph test, passed it with no deception, and then was fired, a potential employer would assume he did not pass it. It was partly, the Stash House case part, JPL's fault that he was in this situation, but the rest of it wasn't.
It is very difficult for even an experienced lawyer to go out on his own; I have known of several ex-prosecutors that have tried. There is a lot of overhead, and Luna wouldn't have a client base. On top of that, some insurance companies that will pay for legal services will not deal with a single member firm; I have seen that first hand. Joining a firm is different, but he would have to be hired.
It is not correct that a murder charge was dropped or filed against either defendant. There was an allegation that could have been used in sentencing. There is a question if the victim's family even knew about that. The agreement was that it could not be used in sentencing. That was the kind of agreement DiBiagio did not like.