Thanks all for the great comments.

Normally, corns are the UNpickiest eaters there are! My ghost male will eat any rodent you put in front of him in any form and my new Lavender female is also a ravenous eater.
I did have my ghost boy go 'on and off' food for about two months...but he would eat one week and not the next, so he was still taking food. Eventually he went right back to being a pig and actually wants more. So, when my adult Amel male started refusing, I thought he was going through the same thing. But he refused EVERY meal offered for a full two months or more!

Luckily, he only lost about 31g or so total from this. And I'm just really glad he ate again, even if he refuses next week. I want to breed him with my Lav girl this spring for some opals.