Try putting him in a smaller tub (Advisable anyway to avoid substrate ingestion) and then slowly moving the pinkie around infront of him...it works for mine, and he's a bit on the frisky side.
Failing that, you can try washing the pinkie with soap, braining it (Putting a hole in it's head to let the scnet out), scenting it with Anole, tuna juice, chicken broth etc...failing all that, leave it overnight in a small dark tub (With airholes) with the pinkie and hope for the best.
Best of luck to you :cheers: