Guests unable to access files they upload

Good morning. I’m running NC 17.0.1 in Docker (great version number btw, I may never update it again).

I have a situation where we want to use Nextcloud for vendor bid submissions. They need to have time-limited write access to a private shared folder. So what I’ve done is set up a group folder, within that there will be a folder for each project, and under each project a folder for each vendor’s proposals. For the vendors I created a guest account and shared their individual folder with them. At the time of the bid deadline, we can unshare the folders, make the shares read-only (preferable), or delete the guest accounts.

One issue I’ve run into in testing is that in this setup, the guest account gets access denied when trying to open a file they uploaded to their shared folder. They are unable to open, delete, or overwrite the files. They can upload new files just fine. The share permissions are correct. The exact error varies by what they try to do, for example trying to upload and overwrite the file says “Forbidden” in the top right corner. Trying to open it goes to a full screen error that says “Access to this resource is forbidden for guests.” Giving the fest group access to the group folder doesn’t fix the error, but this is also a non-starter because vendors must not be able to see each other’s proposals prior to the submission deadline.

A regular account with access to the group folder is able to manage the files normally with no issues.

A non-group folder shared with the guest account has the same issue. Unchecking “Limit guest access to an app whitelist” also does not fix it.

Any ideas what could be causing the access denied for guests?

Any thoughts on this?