The veneer is still made of Sycamore ( I've seen balsa as well). That's still wood.
I turned some old growth Sycamore ( from the bottom of the lake stock) lumber for shafts. They have defects in different colors. Some disappear after a cut, some surface after a cut.
Bryan would have rejected that veneer if he saw the defect was there before he even glued, I bet.
But, to borrow someone else's line, God made wood, Bryan made the cue.