Keep pushing with the relevant authorities. There is a difference between “We are not intentionally restoring comments” and “We certify that we have forgotten all of your info”, and that’s what these authorities enforce.
It doesn’t matter if Reddit’s inscrutable back end makes it difficult. That’s Reddit’s problem, not yours. If they want to do business in the EU, they either have to comply or pull a Meta and stop serving EU residents entirely.
They had a third option, to treat their users as human beings and not dumb fucks to exploit until they want to leave (and forget they ever went there), but they declined to use it.