Originally Sana was offended by the disrespectful way the prince was written about in the strategy guide. But after learning how he would wreck her friend's family, she let him have it on the stage. Maybe this will be the wake-up call that begins his character development arc.
There's no time travel. It isn't a stable timeloop. She just too good as a fortune teller that she invoked the ancient trope of the profession, The Self-fulfilling Prophecy.
She done goofed, but the situation might still be salvageable. She needs to confront the Prince, tell him she isn't asociacted witht the tavern. She might need to apologize and roll in some sort of explanation too.