Comment 7 for bug 1984193

@Brian, indeed downloading and flashing a new image overcame the casper-md5chck errors and the NVidia proprietary driver was installed.

That piece of the syslog caught my attention:

Aug 10 20:08:31 ubuntu ubiquity: Unpacking nvidia-settings (510.47.03-0ubuntu1) ...#015
Aug 10 20:08:31 ubuntu dbus-daemon[2445]: [session uid=999 pid=2445] Activating via systemd: service name='org.freedesktop.Tracker3.Miner.Extract' unit='tracker-extract-3.service' requested by ':1.27' (uid=999 pid=2681 comm="/usr/libexec/tracker-miner-fs-3 " label="unconfined")
Aug 10 20:08:31 ubuntu systemd[2433]: Starting Tracker metadata extractor...
Aug 10 20:08:31 ubuntu ubiquity: Selecting previously unselected package vdpau-driver-all:amd64.#015
Aug 10 20:08:31 ubuntu ubiquity: Preparing to unpack .../32-vdpau-driver-all_1.4-3build2_amd64.deb ...#015
Aug 10 20:08:31 ubuntu ubiquity: Unpacking vdpau-driver-all:amd64 (1.4-3build2) ...#015
Aug 10 20:08:31 ubuntu dbus-daemon[2445]: [session uid=999 pid=2445] Successfully activated service 'org.freedesktop.Tracker3.Miner.Extract'
Aug 10 20:08:31 ubuntu systemd[2433]: Started Tracker metadata extractor.
Aug 10 20:08:31 ubuntu tracker-extract[5820]: Could not get mimetype, Error when getting information for file “/usr/share/applications/nvidia-settings.desktop.dpkg-new”: No such file or directory

Nvidia Settings was supposed to be installed, but it was not. The driver was, which is great!