At this point, they might as well re-purpose the game for PS4 as a launch title. It could then have Evergreen sales for entire console lifecycle instead of just the end of it.
Zelda Twilight Princess is the highest selling Zelda game to date (released as launch title for Wii)
Zelda Skyward Sword is one of the lowest selling console Zelda game to date (released in last year for Wii)
BTW, Shadow of Colossus also released near end of PS2 lifecycle and therefore didnt have the kind of success that games like GTA 3 had which released earlier.