Screen Sharing issues Google Meet, Slack

Greetings,

On a new Macbook Air, I am trying to share my screen in both Google Meet and Slack (Slack screen sharing works with other organizations just not with mine) without success. I have added the apps in Privacy and Security and am selecting the correct screen before attempting to share yet the final step directs me back to updating my security settings. The apps that are not working are selected and toggled to the "on" position so I'm at a loss as to any corrections to make.

Zoom seems to be fine.

Google Meet allows me to go through the process of selecting the screen I'd like to share, and yet when I click the final button to share, the system prevents me from sharing.

The most perplexing of this issue is that within Slack, the green border that indicates what is being shared (entire screen, tab, etc.) is there yet my colleagues report that they only see a black screen. I am able to make screen sharing work with a friend who invited me to his Slack channel which is not a part of my organization so that I could test the settings and see where I was going wrong. On his Slack channel, everything works fine. This leads me to believe that it's probably not the security or privacy settings or it wouldn't work with this other Slack account.

Any directions the community could provide would be most appreciated. Thanks in advance. :-)