Ok when you say this.... What do you mean? It suddenly appeared overnight to be this swollen, it took weeks, it has been the last few months?
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@ERKleRose said the fat pads in his cheeks and casque are full. This is a sign of obesity. Feeding this much at his age is what causes this. Fat in these areas is by no means hard. It is mushy and soft.
In your last post you were told that your compact UVB bulbs were incorrect and were given the link to the correct T5HO fixture for UVB lighting? Did you ever get this? If not this is why his casque more than likely is bending that way.
UVB has to be correct. The correct fixture with the correct distance to basking branch below it.