One Border Collie I had some years ago managed to get into a full tin of Quality Street and there were very few chocs left when I came home. Somebody had, however, been in charge of her that day and I had had numerous, desperate phone calls at work. "She's been sick. She's been sick again. She's been sick all over the kitchen floor. It's making me feel sick."
The person who was in charge at home was a bit squeamish so I could not ask her to clean it up, so had to say, " put newspapers over the patches of sick and I will clean it up when I get home." It was not a pleasant homecoming that night. However, this may be what saved my dog. She had vomited up everything, including all the sweet wrappers, and the person who was at home that day never left her chocholates anywhere within reach of Gemma the dog again.
I would just keep off it. There are plenty of dog treats about.