You can get specific fixing stickers.
https://www.ebay.co.uk/itm/Dial-Repl...EAAOSwhcJWKh5G
As I understand it, soldering is tricky as the heat can damage the dial, epoxy might work I guess.
Dial restoration companies might know more.
Edit. Google found this:
http://watchguy.co.uk/how-to-re-atta...ering-machine/