managed to recover the directories, no thanks to nextcloud.
i hadn't finished pulling all my files off onedrive, so these legacy projects still remained intact there.
everything is moving to my external drive, from which i intend to backup directly to my NAS from now on.
here's another awesome update:
20 project directories, dating back before early 2023, now appear as 0KB with no files- only the directory structures remain.
if you claim to be a cloud platform, data loss like this should be a fucking embarrassment. this is not the first time this has happened.