Forza 1 doesn't have Bathurst either. The file name for the track has FM7 in it.
I'll give you 3 guesses what that's short for and what the current Forza Motorsport release is
Additionally a copyright case won't care whether the track is from a current game or a 10 year old one - the tracks IP legally belongs to it's creator, making any unauthorised copy/conversion/rip illegal - even in the event of that work including additional detail or improvements because it is still built on top of pirated code.
Unused community projects were one thing, especially with the original proviso of the site stating work/dissemination would cease of the original owners resurfaced and complained - But Microsoft and other developers would take a somewhat more litigious view to disseminating 'their' ip without consent.
This is the actual reason that the Re-boot site was taken down if you find the original post made by the site owner after the event.
I believe this is why Srou have always refused to knowingly run on tracks of that nature, because
we could conceivably be taken down. (you'd have to Clarify with Dave - it's his site after all).