In the Mac Pro White Papers …
Where did you read that? And when is it dated?
… an upgraded version of Quicktime Player with additional features for pros.
There used to be a Pro license for QuickTime v3/4/5/6/7. Apple stopped selling registration keys for the Pro version, as of mid 2016. The way it worked was that a key code unlocked the Pro features in the application. It wasn’t separate software. Apple ceased support for QuickTime 7 on macOS in 2018.
The current version of QuickTime (v10.x) doesn’t have a separate ‘Pro’ version.
macOS Catalina 10.15 doesn’t support installing or running the old version QuickTime 7.