It was not in Rodolphus' nature to wait, or to take orders from someone like Pyrites, even if he did have a nice little pub and seemed loyal and ready enough to do His work. At the question, Rodolphus pushed past Argus on the stairwell - he did not wear his mask, he had no reason to.
The sight of Potter, though, stopped him for a moment. He could kill him from here, and there would be nothing to stand in His Lord's way. But He had demanded that Potter be brought alive. Rodolphus took out his wand, ready to rush the lot of them.