At 100 grams he should be able to eat a Rat pink. I would leave him settle a week and then try live mouse hopper. Also try a good sized brown paper bag. Put them both in there seal the bag...make sure neither can get out and put it in the enclosure in case the mouse eats its way out. He should eat then. If leave him be til next week. It should only take a couple weeks and you should be ok. I did this with my baby corn snake and now he eats like a champ. My pied was also picky and hasn't switched to rats yet. So give it time and patients and he will come around.