I have an empty group (folder) from a non indexed structure that I “empty” but continue reappearing in Trash. I deleted from my two current active DT sessions in two Mac at same time but continue reappearing… It is happening since a couple of days.
I kinda wonder whether there was an unfinished sync issue. I’ve just checked here, but I don’t think your empty group has appeared on any of my devices, so we’re both ok