The heat thing is the main way they target prey so yes that is likely the problem. When they open their mouths to strike their eyes can't really see the target I think?

Plus, if his eyes are compromised with stuck shed or wrinkled eyecaps, he will be using the ehat vision more anyway. Which might also explain why he could be feeling insecure and striking at a big heat source ( you ).

But, as I said, pictures would let us judge the eye issue better.