The fight has been confirmed via fightnews & boxrec. Still on FNF but a week later.

Mack vs Johnson is on again | Boxing News

The IBF light heavyweight world title eliminator between Yusaf Mack (28-2-2, 17 KOs) and former world champion Glen “The Road Warrior” Johnson (49-13-2, 33 KOs) has been rescheduled for February 5 in Miami. The scheduled 12-rounder was originally slated for January 30 to take place on the cancelled Mosley-Berto card in Las Vegas. The fight will now air on ESPN2 Friday Night Fights.