Unmet dependencies and cannot fix or install them
It looks like it's trying to install the same files both from oibaf's PPA and additionally from the default Ubuntu sources. I'd be tempted to try simply purging and then re-adding the PPA:
sudo apt-get install ppa-purge
sudo ppa-purge ppa:oibaf/graphics-drivers
sudo apt update && sudo apt upgrade
sudo add-apt-repository ppa:oibaf/graphics-drivers
sudo apt update && sudo apt upgrade
And hopefully that will clear the conflict without anything more onerous being necessary. If not, some investigation will be required.