Bruce Altman's character in this episode is named Robert Leavitt. In all his previous appearances his name is Frank Russo.
There is no Hassidic Grand Rebbe of New York. There are many different sects of Hassidus located in New York and they are each lead by their own Rebbe.
Danny says something about the men being in a sauna. They're actually in a Steam room. (Steam rooms are wet, and tiled. Saunas are dry and usually cedar, or other hardwood.)