The head of the bandit worked with the king of Sham, so he knew a few of the details. The four kings did not meet all these years to avoid raising any suspicion. They relied on using the soldiers who disguise as bandits to communicate.
The prince usually found out all his pry knows when he swallow up their soul. "should we return to Avalo and make a visit some other time?" prince Sébastien asked his mother.
Now that the prince found out about the kingdom of vemus having hidden soldiers, he did not feel it was wise to go into that territory without enough preparation.
"No," the Queen shook her head. She already knew that these four kingdoms will plan something a long time ago. So she had a placed her own eyes and ears. Although she did not ask them to report back to her she was sure they would help her into the venus royal palace without being noticed.