I had this happen once. Hydrogen Peroxide gets the vomiting going pretty darn fast. He barfed it all up very quickly, although he felt a bit unwell for an hour or so after. In his case he had gotten into a bag of leftover cobs, (meant to be donated to horses!) and as it turned out had chewed them up pretty well, so likely he would have passed them O.K., but better safe than sorry!
It wouldn't hurt. When I had the problem I just used the hydrogen peroxide I always have on hand for puncture wounds with horses. it was not a new bottle, but worked just fine. And I always have syringes hanging around as well. Just be careful not to put too much into the mouth at once, and allow the dog to swallow…...you don't want to get too enthusiastic and have them inhale it! Good info on technique here:
If you google search it and ask your vet you find this is a problem for all dogs. The emergancy vet I went told me he has had to do done a dozen emergancy surgeries on dog with corn cobs inside them. Dog tend to goggle things down without chewing so corn cobs can be deadly and should be treat ASAP if they eat one to avoid surgery.
This is what I learned from this.