Opened a joint account with a friend both using their S.S #. Can the whole acct. be frozen because of a debt?

My granddaughter forgot about a unpaid hospital bill and she didn't have any bank acct. A friend told her to give him the check and he would cash it. He opened an acct. with his social security # and also hers (Joint). He claims the lawyers froze the acct. He can't get any money. Is it legal to put a claim against a workman's comp. check? Wouldn't a notice be sent to her residence if this procedure was done? Would his account in a separate account be frozen also?