I'd be tempted to wonder how long Sion is going to be financing the lazy escapades of those two, but I guess when he received the dagger report, he thought they might still be worth it. Even if he needs to tell them to actually go and secure the dagger, not just throw it away and escape.
The foolishness and comedy surrounding everything Ryner and Ferris do is truly in stark contrast with all the morbid politics going on elsewhere. Maybe that's actually why Sion keeps funding them: Reading their reports (drawn by Iris) must be a real breather compared to the oft vile decisions he must otherwise endure all the time.