How/where can my fiance deposit/cash a U.S cashiers check in Portugal/Lisbon? Banks there dont seem to know em

The cashiers check was issued from Heritage Credit Union here in the states and the banks he's taken it to in Barreiro (suburb of Lisbon) and in Lisbon act like they're never heard of cashier's checks, bank cheques, counter checks, etc. They tell him he might as well throw it away. He needs this money and the issuer obviously can't help any longer. Does anyone know where in Portugal is a bank that can take/deposit/cash a cashier's check made out to him from a US bank??