My little guy, heartbreak of no roots

https://m.youtube.com/watch?v=iYLfq65gW4U

I did this but my little guy has not produced any roots and it's in water a couple of months .South facing window. Water changed regularly . Used Clonex .

It's put out a couple of tiny leaves. The end has turned a little black but not mushy ,don't think it's dead.

Any ideas?