McDaniels has three years of eligibility remaining.
Gilliam will rejoin Jim Knowles and Anthony Poindexter Jr. with the Volunteers.
Schlaffer left the program midseason and was the first to enter the transfer portal.
Matt Campbell continues to reinvent the trenches with his latest acquisition.
Mack is transferring away from Happy Valley for the second time in his career.
The junior linebacker will reunite with James Franklin in Blacksburg.