I think it will continue to dry up, and eventually fall off too. I wouldn’t cut it. Just be sure it’s not blocking the vent, which may have been more the case with the chick In the video, but usually not an issue with a duckling. And once it’s dried out enough for some bath time, that will help...
Natalie is me :D
From the looks of the pics, enough has been peeled away, once he’s ready to come out, i don’t see anything holding him in. As long as he isn’t stuck to the membrane, it should be fine to let him do the rest on his own.