It wasn't me to steal it but Bogard I assume, since I tend more and more to believe Mafia has the ability to trigger such events.
If Bogard really gained night immunity he could have claimed it point blank because hosts always notice a player when he gains it during the night, so his defense about night time doesn't stand up. He just made an illogicity slip. Not to mention his version is of no good going by the Bachelor's plot.