Try some LizardMaker. I have had good success with Alterna with that product. If you follow the directions, it doesn't do so well, but I found a little method for it.
Take a day-old pinkie a rinse him off real well with water and dry him with a paper towel. Then wet a small corner of a paper towel with LizardMaker, and wrap the pinkie up in that and let him stay in it for about 15 minutes to get the LizardMaker soaked into his skin some. It is real watery and if you just put it on the pinkie it doesn't stay on very well. Now put the pinkie and the snake in a deli cup and put it aside someplace and leave it alone for at least 24 hours. I've had baby alterna stay in the deli cup with the pinkie for 2 days before they finally ate it. You might have to try that 3 or 4 times at 2 or 3 day intervals before he takes it.
If he doesn't take the pinkie after you try that 3 or 4 times, it might be PinkiePress time before he loses too much body weight. If you have to force feed or assist feed, wait at least a week before you try the scented pinkie again. Try the pinkie every time before you resort to using a Pinkie Press or whatever. Eventually 99% of them will eat, but they will sometimes make you pull your hair out first. (Just think about having 30 or 40 of them to deal with).
I've never had any luck with Gray Bands using the braining technique. It works with other things, like Pyros and such, but for some reason, not Gray Bands. And..what I've found from feeding lizards to baby alterna is that they never want to switch away from lizards once you get them started. I suppose it's better than watching it starve to death, but I'd rather just go ahead and force feed a few times and get them going on pinkies.