I added your 13.2 repo (to my Tumbleweed test install). And then I updated grub2-efi from there. It doesn't actually work. I still get a grub shell. However, hitting TAB now shows a "cryptomount" command available. But I'm not quite sure how to use it. When I look at "grub.cfg" (the file in the EFI partition), it looks unchanged. I would expect that an initial line (perhaps using "cryptomount" needs to be inserted at the beginning of that file.