As soon as Athena activated her skill soul vision, the surroundings around her started to change, she looked at Rio and all she could see were some glimpses of emotions running across his mind. Frustration, anger, betrayal and loss - every emotion looked as evident as different colors in her eyes. Athena tried to probe further but that was all she could see. It made her confused as according to her mastery of skill and Rio's lack of power, it should allow her a pretty good knowledge about everything, and yet all she could witness were normal stuff she could notice from anyone's expressions normally.
When she looked at Rio's eyes, having the panicked look, her curiosity got the better of her, she wanted to understand the reason why her powers didn't work naturally or what was different about him. Psyche's voice in her head telling him "she thought so too" further made her determined. So she closed her eyes and used her main skill, soul eyes on him.