Could you attach the file ~/.cache/simple-scan/simple-scan.log after seeing the "no scanner" message (or run simple-scan --debug). If scanimage -L shows the scanner simple-scan should also be picking it up.
Could you attach the file ~/.cache/ simple- scan/simple- scan.log after seeing the "no scanner" message (or run simple-scan --debug). If scanimage -L shows the scanner simple-scan should also be picking it up.