All left handers playing right handed have to work significantly harder on their bowing technique...

And I rather think the same is true when it comes to playing fretted instruments, and using the "wrong" hand for fretting. But that would have to be set off against the difficulty to be overcome in fretting with fewer fingers using the "right" (ie the left) hand.

Good luck to her whichever she chooses - and either way there's no reason she can't becomes a good player.