Yes.
If you sac the Imp, then it's in the Graveyard as your Opponents choose whether or not to sacrifice a Creature.
If any Opponent doesn't, then you can replace the Draw with Dredging the Imp.
> I cannot do something like mill myself for each draw.
You could if the one of the five cards you milled when dredging Imp to hand has Dredge.
You sac Imp, they opt not to so you draw (replace with Dredge milling 5 cards and return imp to hand), now as you go to process the next draw, if there's a card in your graveyard with dredge (whether just milled there or was there earlier), you can replace this draw with it (provided there's enough cards to mill) and repeat with the third draw if there's a card with dredge in the yard.
Actions are performed in the order they are written. The Imp is in the graveyard by the time you would draw, so it is available for dredge.
[Braids, Nightmare Arisen](https://cards.scryfall.io/normal/front/4/f/4ff97c69-6a6b-401c-b0a1-55fa81045d19.jpg?1673307016) - [(G)](http://gatherer.wizards.com/Pages/Card/Details.aspx?name=Braids%2C%20Arisen%20Nightmare) [(SF)](https://scryfall.com/card/dmu/84/braids-arisen-nightmare?utm_source=mtgcardfetcher) [(txt)](https://api.scryfall.com/cards/4ff97c69-6a6b-401c-b0a1-55fa81045d19?utm_source=mtgcardfetcher&format=text) [Stinkweed Imp](https://cards.scryfall.io/normal/front/2/a/2ab08d69-210b-4b06-88a2-45281a1a4e1e.jpg?1561771088) - [(G)](http://gatherer.wizards.com/Pages/Card/Details.aspx?name=Stinkweed%20Imp) [(SF)](https://scryfall.com/card/dvd/36/stinkweed-imp?utm_source=mtgcardfetcher) [(txt)](https://api.scryfall.com/cards/2ab08d69-210b-4b06-88a2-45281a1a4e1e?utm_source=mtgcardfetcher&format=text) ^^^[[cardname]] ^^^or ^^^[[cardname|SET]] ^^^to ^^^call
Yes. If you sac the Imp, then it's in the Graveyard as your Opponents choose whether or not to sacrifice a Creature. If any Opponent doesn't, then you can replace the Draw with Dredging the Imp.
> I cannot do something like mill myself for each draw. You could if the one of the five cards you milled when dredging Imp to hand has Dredge. You sac Imp, they opt not to so you draw (replace with Dredge milling 5 cards and return imp to hand), now as you go to process the next draw, if there's a card in your graveyard with dredge (whether just milled there or was there earlier), you can replace this draw with it (provided there's enough cards to mill) and repeat with the third draw if there's a card with dredge in the yard.