ZD, I think everyone says going into the actual sanctuary is a problem, some are meikil on other rooms in the building.
At least once I was at a wedding at one of them with Orthodox Hashghca and the wedding itself was in the sanctuary with seperate seating. if you didnt know beforehand that it was conservative you wouldnt have known it then except for the prayer books that were left in the Pews (They were not used for this wedding)