Assist fed for first time.

[Lord Sorril]

I’m beginning to worry that maybe they are just somehow unhealthy snakes? They have no feeding instinct.

Don't be discouraged. I have never had a ball python hatchling I could not get to eat on its own, but, I have assist fed for up to 6 months. The non-eaters turn out just as healthy at the others--sometimes a little smaller due to the slow start.