firmware-mediatek in Debian experimental has a version of 20250708-1 so I tried that without success. It doesn’t seem likely that getting the files from git at the above link will have any more success.
So, probably a different wifi card is required. I’m hesitant to do that without any reports of others having success. I know that Framework test with Fedora and Ubuntu. Are there people having success there, with the MeidaTek card or others?