What is his current size? Depending on the size you can even go smaller, I breed hognose and generally until they reach 20 grams I keep them in a tub with the following dimensions 12" L x 3" W x 2" H (part of my colubrid hatchling rack) or in a 2.7 quarts tub 11.50 x 7.38 x 3.25 Inches keep it on aspen at least 1 to 2 inches preferably the fine shaving.
Other scent that have been great for me are anchovies and toad, and of course but not list offering live which I know is problematic if it is a very small animal, finding live pinky can be difficult.
Males are notorious to go off feed actually a lot more than females, and I have seen this a few times when a male is shipped out and it will refuse to eat for his new owner.
Now assisting is an option if the animal is in bad condition or has never ate before however it's far from being easy (usually done with adult pieces of tails) and not something I would suggest, the animal knows how to eat and has ate before (do you know how many meals, I for example don't let them go until they have at least 10 F/T meals which put them easily at 15 meals or more before they are ready for their new home.)
The last step if all fails is to cool him down (brumate) it can kick start their feeding once out of brumation.
And of course make sure to contact your breeder as well so he can give you some more insight since he produced they animal.