Except that they didn't "accomplish what Blizzard could not". Their server was not a Vanilla server, it was a hacked-together emulated APPROXIMATION of Vanilla from YEARS of spotty research on various portions of Vanilla that no longer exist except in video & web archives. It was also 10 years AFTER its time. (Not ahead of it.)
It would take Blizzard a LONG time and a LOT of resources to rewrite Vanilla's database.
Don't do it, Blizzard.