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.

• 105151pr0001 Animal Body Part, Dinosaur, Allosaurus Head with Dark Tan Print this part is a pair of it
• 21144pr9999 Animal Body Part, Dinosaur, Indominus Rex Tail, with Spikes and Dark Blue Print this part is a pair of it
• 68444 Animal Body Part, Dinosaur, Indominus Rex Arm, Right, with Elbow Spikes [Plain] this part is a pair of it
• 68445 Animal Body Part, Dinosaur, Indominus Rex Arm, Left, with Elbow Spikes [Plain] this part is a pair of it
• 98162pr0099 Animal Body Part, Dinosaur, Tyrannosaurus Rex Leg, Left with Dark Blue Spots Print this part is a pair of it
• 98163pr0099 Animal Body Part, Dinosaur, Tyrannosaurus Rex Leg, Right with Dark Blue Spots Print this part is a pair of it