Have you tried leaving the pinkies/feeders with him in the cage (and giving him privacy)? It's also important to insure that f/t's are warmed just right....not too hot, and not to cold. Not sure it will help, but I thaw my feeders in soiled mouse bedding, and then take a blow-dryer and scent the room with the feeder for about a minute prior to offering it. Here is a link that may also be helpful ....
http://jkrballstreetjournal.com/2014...-eating-again/