First off, the thing you play in Uncharted 4, based on video evidence, is a complete remake. That immediately disqualifies it as "Crash 1". Whether it uses the same scenery models or not, it's completely remade from the ground up.
Secondly, Sony has a publishing contract for Crash 1,2,3,TR, and Bash. They publish those games. They do not own rights to them. That is why even though they hold that contract, and Naughty Dog developed the first four and created all the art, they needed to list Activision as the owner of Crash in Naughty Dog's art-book.
And third, It's Activision's PROPERTY. Whether they say it's cool or not, Sony would be required to list Activision's ownership of it in the credits.