Please disregard. A forum post recommended waiting a few hours and checking again. That seemed to have worked.
Hi there. Universal Ornaments such as the Pandemonic set from Eververse can be applied to any set of legendary Armor 2.0. Your Titan does not appear to be wearing any legendary armor, so this may be why you're not seeing the option to equip your Ornaments. Please equip a legendary armor piece that has an elemental affinity ( when inspecting it, it will have a 1-10 stat with a specific element that corresponds to the type of mods you can equip), inspect it, tab down to the Appearance menu, and see if your Ornaments are available.