Intrepid Paleontologist

Intrepid Paleontologist must be under your control in order to start casting a Dinosaur creature spell using its last ability, but it doesn't need to stay under your control throughout that process or be under your control as the spell resolves. If, for example, you sacrifice Intrepid Paleontologist to pay an additional cost of the spell or it's destroyed in response, the spell will still resolve normally.

Finality counters aren't keyword counters, and a finality counter doesn't give any abilities to the permanent it's on. If that permanent loses its abilities and then would go to a graveyard, it will still be exiled instead.

Multiple finality counters on a single permanent are redundant.