I just got a ball from petsmart that looks just like that skinny & the skin is hanging, I also got another one last week who is also skinny but has a little more weight on it. Like you I couldn't just leave them there. & the "reptile expert" at my petsmart wouldn't even answer my questions. But anyways I fed the one I got last week, but still haven't been able to feed the one I got yesterday. I will as soon as I can. I haven't had snakes very long, I've had my first ball for about 3 months now. & I just got these 2 from petsmart. I guess anything that can help you would help me to. I wish you the best of luck.