There seems to be a bug preventing Right Eye mods of any rank being used in secondary utility gear.

As can be seen in the screenshot, the Spell of Takofanes, Ascii's Precision, Kigatilik's Wrath, and Ripper's Might mods are all properly able to be slotted into the Cosmic Vision of Rage. I am able to slot the Right Eye into my primary utility gear, but at rank 5 and below it should be usable in appropriate secondary gear as well.
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Epic Stronghold
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