If RDP webcam passthrough is not working in a Zoom session, you can resolve the issue with a few easy steps.
Open the Windows Start menu.
Click Hardware Settings and then the Audio/Visual dropdown.
Scroll down and toggle the Camera Privacy Mode to the off position.
For macOS users, look in System Preferences as shown in the following screenshot.
The issue may have been that you need to allow access to the Zoom Remote Desktop camera. Just enable it and you’ll be able to use the camera in your RDP session.