When joining a meeting with multiple participants, my image shakes. It is distracting to the participants and I need to shut the video. Is this a problem with Zoom, the camera or Internet resources?

On a recent meeting with only one participant, there was no problem. 

How can we manually\automatically push out event reminders to the attendees prior to the event?  We did find the listing of our attendees and you can do this individually, but we couldn't see a way to do this on an entire group scale.

For example - we open the event.  We want to send out an email to all attendees 3 days before the event, and another email at 7am on the morning of the event.

Does anyone know if there is a way to pass information from the attendee's registration questions into the email they get after the session and/or the email they get confirming registration? I want to include the employee ID that I collect at registration in the email so they can be aware and check for errors.

For context:

We require employees get a certain amount of continuing education during a year. The employee ID entered at registration is how we load credit into our learning management system. It should be relatively painless but we regularly have people who have typos and then panic when it comes time count continuing education credits at the end of the year.

I am an attorney in Las Vegas, Nevada.  In May 2023, I have a Settlement Conference for a case where my Chinese client will appear by Zoom.  The account is a U.S. Government Zoom account.  Has anyone had an issue where the Chinese person could not log into a Zoom meeting on a U.S. Government account?