The only problem I really have with this is that it's quite simple and follows the TLK plot pretty much the whole way through. To make it more interesting we should have a twist somewhere in the plot. Something that's unexpected and that isn't part of the TLK storyline. Maybe when Nala comes to the jungle and meets Simba again, Simba refuses to go back. Nala can't persuade him so she runs back to the Pridelands, very angry and melancholic.
In her rage, Nala blurts out Simba's location to Scar, forgetting entirely what the consequences would be. Scar almost immediately sends some Hyenas/lionesses loyal to him to the jungle to find and kill Simba once and for all.
That's something that I made up quickly. I don't know whether it'll work
