Re'Kha had been spying on others during the time she was waiting for the three ladies behind the counter to count the money Ki'Nua had brought. In this time, she noticed the sheer quantity of money submitted by the others.
It was easy to determine because the lady behind the counter in every counter announced the money that had been submitted. It wasn't audible to anyone else due to being blocked by the walls on all sides, and the whisper by the ladies.
But to her, it was as if they were speaking in her ear. She could easily hear them. So, it was easy to know that the treasures appearing this time would have incredible value. And, quite a few among them were those that were able to elevate a Harmoniser's strength.