Ball python jaw too short?

[Zincubus]

That is an under developed lower jaw.
If she is eating then I wouldn't worry about it other than the fact that the breeder should have made it known to you.
It will not prevent her from eating.

True enough !

I saw one one similar to the description on sale in the uk , it was either very cheap or free , just can't recall .

I'm guessing that it shouldn't be be bred from but I'm not 100% certain on that point .

The one I saw looked a little like a baby shark from side , it was hellishly cute looking .