If the 52 - 52°F was the cabinet temperature, and the steaks were handled properly in the past, and if you refrigerated them quickly out of the smoker, you are alright. The danger zone is above 40°F and below 140°F. The maximum recommended time in the danger zone is 2 hours at room temperature (68°F). Also smoke has some antimicrobial properties that may extend the time in the danger zone a bit, but don't solely rely on that safety.
Most only cold smoke for 40 minutes to an hour.