When do you want to start?
Assuming very conservative butterflies with the royal marriages, it's far easier before he's born, but
this shows he's at least 11th in the line of succession at the death of Charles VII and probably a fair deal lower.
If you kill off Charles VII in battle in, say, 1434 (so the English are starting to lose) and the dauphin dies of plague (as Charles VI's sons all did except for Chrles VII) you still have Charles VI's brother Louis' sons, as well as the Duke of Anjou and his male heirs, as they descend from Louis II, OTL King of Naples and the older brother of Philip the Bold.
So, it's doable, but it's probably easier to start a bit further back and have some more conservative butterflies. A more devastating battle somewhere in the Hundred Years War would be enough to kill off a few people, though, and it doesn't need to happen all at once. The dominoes coudl start falling in 1433 and he could end up only on the throne in the 1460s. Starting in 1433 you'd only have to have about 10 or so die.