If the full breeding is registered on both sides with a recognised authority (KWPN certainly will be) then the foal should have been pink-papered anyway. My home bred yearling was registered with the AES last year (sire AES stallion) and is fully pink papered although the mare is half Arab/half TB and registered with the AHS not the AES. I just had to send copies of all the mare's registration details to the AES with the registration form and covering certificate.
-------------------- "Horse, thou art truly a creature without equal, for thou fliest without wings and conquerest without sword."