Hi Brent
Manual Focus Controls Logitech C920 One
Logitech webcam B910, C910 C920 and 930e Auto-focus fix. Our Live Home Camera this link. Logitech webcam HD B910 and Full HD C910 and Full HD C920 and 930e all make very sharp and fine images. These are sure elite webcams. All cameras is ubuntu linux support. But both my B910 and C910 cameras are not specified for long enough focus distance. Webcam Settings, adjust exposure, white balance, zoom, focus and other controls for USB UVC camera (Logitech C910, C920, C615, Microsoft LifeCam Studio/Cinema) on Mac OS X. We recently purchased some Logitech C920 HD Pro webcams for our judges in the courtrooms. We use Zoom and the cameras will randomly go out of focus. The quickest way we've found to fix the issue is to go into video settings and toggle HD. I downloaded 'Logitech Camera Settings' and disabled auto focus but the issue still occurs. If you own a Logitech webcam like the popular C920, Brio, C922, or C930 and want more control over the zoom or positioning so you look better in virtual meet.
Obliviously check and make sure to go through the manual of the device as how it sounds with the video settings its in between focus.
Manual Link: https://www.manualslib.com/manual/557029/Logitech-Hd-Pro-Webcam-C920.html
Manual Focus Controls Logitech C920 Online
If all the cameras are doing it then presume its a setup. However I understand that you are using Zoom which before when we've tested between Zoom and Teams the MS Teams has been better for video capability so unsure if there might be a Zoom setting conflicting with the cameras but it's hard to say.
Logitech Webcam
By any chance do the cameras have an option for a new driver install or are they update to date? I don't think the driver would be the case but you could that a try and see where you get