There is a workaround to this to have the mod working in Official Realm despite its unsanctioned status that works for myself.
When you start the game up make sure to have the Scoreboard Tweaks mod Checkmarked AND the “Auto-disable Unsanctioned Mods in the Official Realm” and ‘Accept’. The warning about having an unsanctioned mod will go away and you can launch the game. Though the Scoreboard Tweaks mod is not disabled upon starting the game.
Tested it multiple times and works for me seeing friendly fire status in quick play games or when playing with bots.