I had this issue too.Sometimes the commands would work and sometimes they wouldn't.If I used the same command several times I could get it to work then but it wasn't reliable enough to make the fight any easier.I just kept the robot locked down with freeze spells and summons while I picked off the mages and then concentrated fire on the bot.Hard to tell whether or not the controller is bugged or if the devs wanted it malfunction.I'm on PS4 too so it might be a platform specific bug.
