My girlfriend (over 18) is estranged from her parents, but recently discovered money in her name in the form of stocks. She sold the stocks, but the company that handled the transaction sent a check with her father's name as well (with an "and" between the names). When she went to deposit the check, they demanded to see his ID and signature as well (which she obviously doesn't have).
She endorsed it already (not knowing this would happen), so she can't mail it off to him (otherwise he will cash it in his account). She's reasonably certain he won't do anything to help her get this money.
The issuer of the check said they can't/won't change it to "or" so now the money is basically in limbo. What course of action should she take? Is it possible for her to, say, un-endorse the check until she gets the other signature? Can she somehow be guaranteed that she can access the money and he won't dispose or himself cash it out?