Nice work! I used the exact same foam carving tool for my current enclosure's background which made the carving process much more fun than with regular household utensils. I've witnessed dragons climb some quite vertical surfaces if their nails can find enough purchase but I'm sure the beardie will enjoy the extra retreat space the cave now offers.
There is something wrong with my beardies left eye!! I included a picture where it shows what her right eye looks like then the others are what her left eye is. She always has it closed (as much as she can) and she finally opened it for a bit when i misted her. I don’t know what i could be doing wrong and it’s not from sand because she doesn’t have it in her cage.