Hi!
Thank you, I was able to log in now 🙂 I have found one issue, there was a content type filter enabled, but not in use (Frontend search settings -> Conetnt type panel). I have disabled it, now the user results should be visible as well.
I have also tested if the groups are returned, and they are in the results: https://i.imgur.com/vjVpUKt.png
I think that should be fine now as well.
I looked for Group Activities (posts, comments) to test, but there are no activities within the groups yet, so I was not able to confirm if that feature works okay, hopefully it is.