Is that what they call "In the bag"?
"In the bag" goes back to small game like birds hunters would shoot and put in a bag. At that point it is a done deal, secure, etc. Before that it was a bird in hand, which we all know is worth two in the bush. Later still at dinner eating the bird is putting on the feed bag, which was what they would fill with oats and strap on to a horse. This all may have bagged you more than you need. Which is fitting. The Volcano was a very big bag.