I know one trick for making dogs throw things back up if that's every an option. A vet actually recommended it.

We did this for a big 100 lb newfoundland after she ate something she shouldn't have. We gave her a big tablespoon of 3% hydrogen peroxide every 5 minutes until she threw up. We didn't go beyond 5 spoonfuls though. luckily she threw up at 5. But she just kind of gurgled and burped for the first 4.

I know that if dogs eat something dangerous like a hook or sharp bones you probably shouldn't make them throw up. But remember the peroxide if the doggies get into other things that they shouldn't that can come back out the way they went in.