Maybe try different size crickets. I've had babies that won't eat the crickets if they are a little big, and I've had babies with a cage full of small crickets that will chase down a large cricket if I throw it in. Good luck with the little guy.
I thought as my first post I'd introduce you guys to some of my boys. Here is are a few photos:
6 month old ambilobe
7 month old ambilobe
9 month old ambilobe
Great to be on the forum, and hope you enjoy the pics.