No I am not prompted for the rescue code when scanning the QR code from the backup/export that requires a password to be entered. When I export the more secure way which requires a rescue code then I am prompted for the rescue code.
From what I've heard so far, and if you are certain that you are using the correct password and there's also nothing wrong with the way you enter it (e.g. accidently having a space added when copy-pasting etc.), there indeed seems to be somehing wrong.
Of course, in order to debug this issue, we would need to look at that particular identity. Is this identity in active use, or can you imagine giving it up and creating a new one? Unfortunately, without the corresponding password, even the identity will be of limited use. So if you could provide both, it would of course be great. If that's not a problem, you can PM me with the details and I'll look into it.