Variants of a mold are catalogued separately, so each one has its own sets and minifigs. Check these too if something you expect is missing here.

• 30459 Animal Body Part, Dinosaur, Tyrannosaurus Rex / Spinosaurus Head [Plain] this part is a print of it
• 40390 Animal Body Part, Dinosaur, Tyrannosaurus Rex / Spinosaurus Lower Jaw, with Pin Pair of this part