Sumato and Mushi were the first to start the search, searching around the room for any hints or clues as to what buttons should be pressed. Mushi, through his searching, didn't really find much of anything. Sumato, on the other hand, seemed to be much better at spotting things than Mushi did. As she looked around, she would spot something incredibly hard to see. A tiny button on the base of the wall, something that one would have to be looking at quite closely to see, yet with her keen eyes and sharp mind, she was able to see it and spot it as a button that could be pressed since it blended into the room quite well. 

Whether or not she chose to press it is up to her, but it could reveal a clue. It could also be dangerous and be part of a trap as well, so whether or not it should be pressed would be up to her, or the rest of the party if she told them about it.