He is running on a schedule now, and the deadline is unknown. At some point someone will notice that missing guard and then it will all be over. The trick is find Tony and get out before that happens.

At least there is no trouble about searching the place. He found the appropriate room with a pair of binoculars, from the ninth floor of a building four blocks away, before he went to fetch Obadiah. (Oh, yes, he was tempted to go in by himself. But it would not have been worth the risk.) He proceeds directly there, opens the door, and slips inside.