Is there a way to download content from the community workshop using the steam download_depot ?

Are you on windows or linux, if you managed to fond the dlc files, you can most likely(not 100% sure it works with delisted) use creamAPI to make steam think you on them. On windows I’ve used CreamInstaller, which is a handy GUI that does it for you. I seem to recall I did it on my father computer running ubuntu, but don’t recall exactly how.

You are easier to track with Adnauseum

Even dumber than that, when their activation method fail, the support uses massgrev to install windows on costumer pc