No webcam connected and VDI plugin in connecting status

A user reports have no camera function during zoom meeting.  He uses Zoom VDI client on a remote desktop server host.  I have contacted zoom support and was advised to update the VDI plugin (for Azure Virtual Desktop and Windows 365 Cloud PC) on his thin client to the latest (5.16.0).  I am uninstalled, rebooted and reinstall both the plug-ins and the client VDI client but still did not see the camera being recognized.  I logged on the client, navigated to statistics >  VDI and found that the plugin was in "connecting" state and the statistic disappeared in seconds.  I checked my VDI client (also 5.16.0) on my desktop.  The VDI plug-in status is in connected and it recognized my webcam which is the same brand as what the user has and video works.  I have even tried a lower version of the VDI plugins (5.15.2) but zoom still does not recognize the webcam.  I also made sure the defender firewall was set to "allow" on zoom meeting and zoom conference.  I am not sure what else to try and how to get some sort of logs from zoom.  Please help.  thanks