Re: dawn, brock and ash's pokemon
I don't think Ash will evolve his Turtwig and Chimchar to the last stage.
As you can see, Ash has only evolved two starters to their final stage. They both may evolve but I'm not sure. The Chimchar may become Infernape and face off Paul but then again it may remain as a Chimchar and face it in that form and defeat him. Grotle may not evolve to the final stage like Bayleef.