Apparently this has been a issue for a while, as VMware has a KB about it. If one has their cluster set to auto-update VMware Tools, and that VM(s) is(are) shall we say "queued" for an update, and if it comes time for patch Tuesday to come around and that VM reboots, the machine can come back without a NIC. Apparently VMware Tools gets uninstalled, and not reinstalled, so there is no VMware specific drivers on the machine. One must use VMware remote console and manually install VMware Tools. Unfortunately, IP information is not retained! In a few instances the VMware Tools ISO wouldn't mount through the menu in the VCenter GUI doing the "Install VMware Tools", so one would have to manually mount the ISO in the console. So choose to manually upgrade VMware Tools, then do Windows Updates.
https://blogs.vmware.com/vsphere/2020/09/introducing-vmware-skyline-health-diagnostic-tool.html
