It may have to have its legs hobbled sounds like one is splayed. do you have any poultry vitamins? you might try giving the lil one some fresh water with some poultry vitamins in it to get it started with they usually don't want to eat for the first 24-36 hrs. so I wouldn't be too concerned with...
Good going hubby. as for the egg I really don't know and not many here with experience any more, summer is upon us, I'd keep an eye on it though if it goes bad it could blow up and ruin the rest of your eggs. I don't incubate in a bator so other than what I read in here I am pretty clueless.
Have you read this https://www.backyardchickens.com/t/491013/goose-incubation-hatching-guide-completed
as for candling I use an LED flash light in a dark room it works great. as for a candler go on line and type how to make one I bet you get all kinds of links come up.
We haven't seen Pete this year, and looks like just about everyone is off somewhere else today, I looked on line and found sone links that may help until someone who has more knowledge than me comes in. Hope they help...