Based on this 247 article, the following true freshman are not eligible for a redshirt this year: Tayvion Robinson, Keshawn King, Norell Pollard, Mario Kendricks, Doug Nester, Bryan Hudson, Brion Murray and Nick Gallo.
The following players can play in two games and maintain their redshirt status: Tahj Gary, Jesse Hanson, JR Walker, Jaden Payoute, Dean Ferguson and Amare Barno
The following players can play in three games and maintain their redshirt status: Joshua Fuga
The following players can play the rest of the season and maintain their redshirt status: Jacoby Pinckney, Nyquee Hawkins, Elijah Bowick, William Pritchard, Jaden Cunningham, Knox Kadum
By my count, there are 13 players that may be available against Pittsburgh if Fuente feels inclined. I'd be interested to see how Fuente manages the guys in the middle that could make a difference (e.g. Payoute).