The way to handle parts with bad licenses is to remove them in %prep. This is perfectly sane, and the official way for e. g. unbundling system libraries. Therefore, the licensecheck should not be applied to the sources but rather to what's in BUILD after doing rpmbuild -bp.

I classify this as defect - reporting licenses removed in %prep is just wrong.

Don't bash me to hard if I read the code wrong and this is already fixed.