At that point in time, Vicarious Visions had worked on various ports for the Tony Hawk series. However these games where either on weaker hardware or portable systems. I'd say the most notable work was them making SK8TELAND for the DS, which took the themes of American Wasteland and heavily stylised them to be more comic. Heavy line work, flat shading. I dug it.
Problem is that THUG and THAW implemented adjustments to the physics that had been present since THPS3. It's why if you go back and play THUG, many people consider it "floaty" compared to the rigged nature of the THPS games. I think that is in part due to them allowing you to dismount the board.
The interview they had indicates that they have the source code for THPS1. But as seen with the Crash ports they made, they'll likely brute force everything to be around one engine.
A dev team that also has history with the Tony Hawk code is "Toys for Bob" who'd go on to make the Disney Skateboarding game for PS2. I wouldn't be shocked if they take the reigns of 3/4 HD whilst they have Vicarious Visions prioritise a new Crash project.
https://youtube.com/watch?v=bxuL0VUPTf4