Just found this... it might help you or a future admin who's attempting to secure a system:
gsettings set org.gnome.desktop.lockdown mount-removable-storage-devices-as-read-only false
gsettings set org.gnome.desktop.lockdown disable-command-line false
gsettings set org.gnome.desktop.lockdown disable-log-out false
gsettings set org.gnome.desktop.lockdown disable-printing false
gsettings set org.gnome.desktop.lockdown disable-lock-screen false
gsettings set org.gnome.desktop.lockdown disable-print-setup false
gsettings set org.gnome.desktop.lockdown disable-user-switching false
gsettings set org.gnome.desktop.lockdown disable-application-handlers false
gsettings set org.gnome.desktop.lockdown disable-save-to-disk false
gsettings set org.gnome.desktop.lockdown user-administration-disabled false