Anna I am so sorry. :( I know how much that must hurt and your heart hurts too because your Bon was responsible (indirectly). All I can think of is that the positive thing that came out of this was to learn that they need to be separated in the future at feeding time. This same thing could have occurred while your petsitter was watching them and you would have felt twice as bad had she been hurt. See, there is a silver lining to every cloud I guess.
Years ago I had a different standard poodle (Whitney) and miniature poodle (Ashley). They would eat at different speeds and when Whitney finished early once she went close to Ashley's bowl and got a nice growl. I separated them for feedings after that. When it comes to food, sometimes their common sense goes out the window. ((((Hugs)))) to you and I hope your leg heals quickly.