1. Ruto would reject any and all attempts to steal her soul. She's seen examples of souls without bodies, and bodies without souls, and all of that would just be a major no-no in her books.

2. Ruto is canonically immune to exactly this sort of influence thanks to the Echo. Like, put her full-on into the light of the Dawn Machine, and see a flare of her own Light around her completely deflecting the influence from touching her, and possibly even a few people directly behind her.

Spoilers: Go ahead and spoil! I haven't played the game, and likely won't.