Technically the eggs won't hurt each other. If you can do it without too much humidity loss, then I say do it if you really need to. My ducks were alot rougher on the other eggs after they hatch than the chicks are, so they will bowl them around pretty good! But still shouldn't harm them. Why do...
So you are saying that a large incubator manufacturer has a "GUIDE" out there that has a number of things wrong with it, but you can't tell us what's wrong? I checked their website and the same guide is still there, no changes. I would be happy to delete the pic if I believed it were inaccurate.
I've never hatched geese, but according to this chart, they could take a bit longer than the ducks, but are in the same basic range. Same temp and humidity recommendations, so I would think they would hatch together. I hatched ducks and turkey together.
As far as the one duck egg on day 5...