Arrested at work

My kid brother is 19 and works for a large company that sells electronics. The other day, he was called into his supervisor’s office, accused of helping a random customer steal a dvd player, was interogated, then fired and arrested.
He was told there was surveillance tape but when he asked to see it, he was shown a photograph of the woman leaving the store. The incident in question had occured about a week earlier.

The head of the security department interogated him off and on for well over an hour. There was another employee present.

My brother says he didn’t admit to doing it. He has also never been in trouble at work before. But then he tells me that the head of security made him pay for the dvd player, saying that it wasn’t an admission of guilt. Is it, though?

When I asked him why he paid for it, he said he had been in there for an hour at that point and that she kept pressing him to do it and wrote out a note that said he’s pay in three installments and had him sign his name/address. Then she left. Half hour later, she came back with the police and they arrested him.

He had worked over six hours before she brought him into the back room and he was told he lost his pay for the whole day. About 20 minutes after his shift ended, the police showed up.

He has a court date in a month.
Is all of this legal? Do we have any recourse? How should we handle this? And mostly, is my fear that he may have admitted doing it a done deal?

Thank you in advance for your help.