Never take him out un fed.Would you go for a days work on an empty stomach?? i think not!! Patience is the key, find a small ish bury you know to be occupied and let him loose .Don't be in a rush to pick him up, let him mooch and find his own way .Sure there are ferrets that are better than others but in over 30 years ive never had one that wouldn't go to ground!Get some pipe etc at home let him play in/out of it etc it all helps.Sure he may never be the best worker but i bet given patience hel go to ground.Atb