You can remove those packages, they got dropped from repositories and are not in AUR.
You can use
pamac update
Because IMO is better to use the polkit … so it will ask for password
You can then try to run
sudo rm /var/tmp/pamac/dbs/db.lck && sudo rm /var/lib/pacman/db.lck
Are you on unstable or testing branch?
A few changes got made to libpamac so that users can use sudo with pamac, aka run:
sudo pamac update
So, it seems the db.lck is created in two places …