Hawkins is featured on three tracks that appear on the final version of the album. He is also listed as a co-writer on those songs.
"There's a bunch of other stuff with Ozzy and Taylor, as well, that's going to be used for another thing," Watt told Rolling Stone.
Hawkins was one of two drummers used on Patient Number 9, the other being Red Hot Chili Peppers' Chad Smith, who also performed on Ozzy's previous album.
Patient Number 9 is stacked with special guest co-writers and performers, including Eric Clapton, Jeff Beck, Tony Iommi, Zakk Wylde, Mike McCready, Robert Trujillo, Duff McKagan, Chris Chaney and others.