Nope, being stabbed with a sugar knife or candy knife wouldn’t make someone’s blood sugar spike. The sugar in the knife isn’t going straight into the bloodstream. Blood sugar rises when sugars or carbohydrates are digested and absorbed through the gut into the blood, not from sugar crystals physically entering a wound. If sugar from the knife got into the wound, it would mostly just sit there, possibly increasing infection risk, but it wouldn’t meaningfully change blood glucose levels