While this would not answer your question, but according to podman maintainers, rootful podman with userns=auto enjoys nearly as much security benefits as rootless. (As always, there are nuances to this)

Check out https://github.com/containers/podman/discussions/13728

Maybe you could consider running rootful podman, especially if the OS is immutable.

Sometimes I wish I were like OP, being creatively greedy to snitch lots of money. Then I realize, that requires money and influence to work out… Life.