It really depends what you’re trying to do. Make something citable? Findable? Permalink?

Crossref isn’t the only DOI registration agency. DataCite may be more relevant, although both require membership. Part of this is the commitment to maintaining the content.

You could look at Figshare or Zenodo? https://docs.github.com/en/repositories/archiving-a-github-r...

Then Rogue Scholar is worth a mention. https://rogue-scholar.org/

Sorry that doesn’t answer your question but maybe that’s a clue that DOIs might not be right for your use case?