What happens if Microsoft releases a replacement for a problematic security update? Do we need to uninstall the previous update before installing the rereleased update?

I’ve never known it to be necessary to uninstall the buggy update. Typically, Windows Server Update Services (WSUS) will either silently reinstall the new version of the update or prompt you to approve the update for installation, depending on your system configuration. In some cases, you must rerun discovery for Windows to realize that there’s a new version of the update that needs to be installed on applicable computers. In rare situations, a bug in an update’s metadata will cause Windows to report that computers still need to install the update even after the update has already been installed. This problem goes away after Microsoft rereleases the update with updated metadata.