The Scientist according to Just Blaze was supposed to be the official Jay/Nas collab that was to be on HHID. Nas came to the studio with the some rhyme books and started piecing verses together. Then he got a call from someone, said he’d be back, and never returned.
Just recently said that the track is finished so if its included on Lost Tapes AND still has a Jay verse then that probably counts out Street shyt and Sinatra In The Sands because Nas ain’t putting THREE jay verses on his album, let alone Lost Tapes.
They could always remove verses from any of these songs and add new ones especially considering how long Nas has held onto them.