The flanges on a skyway coaster hub are just pressed onto the steel shell, and it has real fine "splines" round it - it looks like it might be the same on those, as there looks like wee splines around the hub flange on that second pic where it is dished outwards - see what I mean?
Maybe a case of (carefully) using a drift to try push the hub through and away from the flange?
What does the front hub look like inside? is there lots of free space inside and nothing that looks like it might catch on the way out?
Brian