Clue

In the majestic palace with stone columns propping it up, Klein sat in a high-back chair as he lightly tapped the corner of the long mottled table. He first eliminated the method of seeking a Sequence 4 Unshadowed from the Sun pathway.

This was because he had almost zero contact with the Church of the Eternal Blazing Sun. It was very difficult for him to find help from anyone. Secondly, he suspected that an Unshadowed was unlikely to be capable of cleansing the mental corruption in the All-Black Eye. After all, The Hermit Cattleya's suggestion was directed at remnant influences by an ordinary Rampager, and not the True Creator!