Lucifer and Asmodeus didn't look surprised by the announcement. Neither were the rest, as the fallen angels had already informed them about it.
The second disaster.
Lucifer wanted to tell YuWon everything about the disaster, but Asmodeus stopped him. Unlike Lucifer, he still had some lingering feelings toward being an angel and wanted the awakeners to go through the trial themselves.
Hence, Asmodeus didn't want them to interfere much in the trials. Even though they were just as much mortal as the awakeners. Anna was surprised by it because he had actively taken part in the trials in his timeline.