Long story short, I would like to report a copyright violation (per Acceptable Use Policy), but I don’t seem to be able to find the right way of reporting it.
The most appropriate medium seems to be the pypi/support repository but the New Issue form is limited to a handful of categories, and doesn’t provide neither a “other” template, nor the ability to open a blank issue.
I wasn’t able to find a specific contact address in the “Acceptable Use Policy” document either, nor on “Terms of Use”. “Help” only tells how to report bugs against Warehouse, which I don’t believe it is. It also suggests reaching out to maintainers of packages, which we did (and we’ve got pretty much what accounts to a “sue me” response).