FYI The company filed bankruptcy. Chapter 11
I would keep the computer until he gets paid!!!
Most likely your brother will not get the money he is owed. Was he an employee of the company or was he 1099 billing the company? If he was 1099 billing the company then he probably has a better chance because he becomes one of the creditors, at least I believe that would be the case.
You can usually consult with an attorney for no charge to describe the situation, or perhaps a nominal fee. But that would be the way to start. The chances of the right person, to answer these questions knowledgably, even seeing this thread are slim at best.