Not gonna spoil Victini's event. You have to pay attention to what a specific character in the game says after you beat him. Otherwise, you can skip Victini's event all-together. So it's important to read everything that's been said.
I feel kinda silly posting this because I was going to put the Obvious choice here. But my friend decided it's best to let the community decide this. So, after an error occured, Castform is out of the hack. So I need 1 last pokemon for the game that doesn't have an evolution to replace Castform's spot. Rotom was my first thought as it has different forms as well. But then I remembered all of the forms have different stats from the original & I don't have the room to add all of em seperately. So I've come up with a small list of pokemon that don't have an evolution & can simply be found in a random area:
Stunfisk
Pachirisu
Durant
Chatot
Carnivine
Audino
Alomomola
Maractus
Standby for the Durant Posts! (I think)
Also, I've updated the pokeList on the OP, adding Wynaut, who I completely forgot about, to Nursery Road with the other baby Pokemon.