Hi! Happy to try to help you. I’m not sure exactly how the wallet selector works in Amethyst but maybe nostr:npub1gcxzte5zlkncx26j68ez60fzkvtkm9e0vrwdcvsjakxf9mu9qewqlfnj5z can help.

In terms of paying for the nostr.wine relay directly - you can also go to https://nostr.wine and make the payment there using whatever wallet is most convenient. You can also copy/paste the lightning invoice elsewhere as needed.