I am trying to troubleshoot an issue for a user that is having issues connecting to meetings

It can take up to two minutes for his connection to the meeting to finish

He says this is recent behavior and is only affecting him within the organization

I tried updating the Zoom client

Removing all appdata and reinstalling

Verified that firewall rules were enabled

He is on a hard wired internet connection

Checked his internet speeds and they are very good

Made sure he did not have any backgrounds enabled

Tried on the zoom website as well, and same slowness is occurring which made me think it was something not related to the application. Kind of at a loss here.
If anyone has some ideas I'd appreciate it!

We host weekly meetings and what is happening with our vendor is outdated registrants.  My concern is old registrants = Zoom Bombing.  These registrants no longer work for the vendor and I need to remove them to prevent access to current meetings, but how?

Is the only way to click each registrant one by to cancel their registration?  HELP!

For a long time, I thought as a host I could centrally arrange for all third party entries into an interview to remain complety invisible for the interviewed person in the interview.  So, not just without audio and video, but also not present in the participant dashboard.  It has always looked that from my point of view, but apparently not from the interviewed person's point of view as I found by accident. Can someone help me out? 

So, I want to interview people for research purposes. And I will disclose to the interviewed person that people may be watching. However, I do not want them to appear in any way shape or form in the dashboard,  with names or anything in screen. Is that possible? and how do I do that? 

Cheers,, Xandra