Mone Chiba may not have won any events, but her combined scores (424.45) are higher than Rino Matsuike (391.36), Wakaba Higuchi (403.01) and Hana Yoshida (390.83). She won silver at the Grand Prix Final, and was in events won by Amber Glenn (combined 425.98) and Kaori Sakamoto (combined 433.09). Those combined scores are the tie-breaker after placements, so she went into GPF with a higher placement than Rino for that reason. She had tougher competition in her assignments and held her own with the third highest combined score. She is scoring well enough with three different judging panels to help Japan keep the three spots that they have going into an Olympic qualifying Worlds.
I'm not seeing where her record is that much weaker than the other women in the GPF. If you prefer to see Rino Matsuike make it to Worlds, that's fine. Everyone has their preferences. But I'm not seeing what makes her record this season that much stronger than Mone Chiba, and I doubt that JSF would see it that way either. If one of the criteria for Worlds is top 2 GPF placements and she is the highest Japanese placement there, it would be extremely difficult for them to not have someone who fulfills that criteria on the team, especially with the consistency that she's shown this season.