Nevermind, I was running Parted Magic on a Virtual Machine. I burnt the iso on a Usb stick and booted my laptop to a true non-virtual Parted Magic session. My internal HDD was recognized and thus I could ATA secure erase my Sandisk Extreme.
Writing speeds went from 10 mb/s to 190. Could not be happier.
Again, thank you for the tips on bringing this flash drive back to life.Â