Is he going to stop her from toddling when she starts falling flat on her face? (hopefully she'll be like my daughter and collapse her legs when she feels herself losing balance and land on her bum instead but my boys never learned that trick, they stiffened up like boards when they felt themselves falling XD) Disbar her from playing on the playground when she trips over or falls off the play equipment? Stop her from playing with other kids when there's the inevitable hair pulling/shoving/full on fisticuffs before they learn to settle with words or at least stop talking to each other? :D

Falling out of the corner is definitely a possibility, but pretty low unless stuffing around. As she's crawling she's probably learned to come down feet first, and if she hasn't figured that out yet you can teach her by sliding her off the bed feet first or putting her foot down when she's navigating a ledge or step.

If that's the way he wants it, he can get up every time she wakes up and pass her over the side to you (even if you're on the cot side) and when you're done feeding he can put her back and settle her :)