I would take my chances and take the money with me. He didn't say where he was going to travel, but if he doesn't want to have the money with him, he could open a new bank account in the country where he is going and deposit the money there. Then when he is ready to come back, he could withdrawn everything and close the account.
Opening a bank account in some countries, especially if you do not have residency, is very difficult. However, would another option be to take the pesos with you and then change them to travellers cheques? Do these even exist any more? Then cash out the traveller's cheques before you come back.