[TheDS1337]

Thanks all for the responds, it seems that the only way is to set sv_cheat 1 during the slow motion and set it back to 0 when the slow motion ends (using a timer like you guys said).

The game mode it's not really a mod tbh it's just some funny maps (coop missions) I found them in workshop but it seems that they won't work in dedicated servers after asking the maps creator.