Have you tried the Legacy roompanel registry key? That worked for my users with the issue when webview2 didnt. Again it isnt a solution but so far that one has stuck for the longest for me
For clarification that was:
In Registry Editor, navigate to: HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\Options\Calendar
Right click on Calendar and select New DWord (32-bit) value.
Set the Name to ShowLegacyRoomFinder and press Enter.
Right click the new key, select Modify and set the Value data to 1.
Close Registry Editor and restart Outlook.