LST not working with prerequisites

I bought a Relic 5 LST from the Era Shipment and used it on Darth Maul to unlock the prerequisite for Sith Eternal Emperor. For some reason, it hasn’t been achieved. Is it because Maul needed to be upgraded to Relic 4, and I just skipped that part by using a Relic 5 LST? Please help, because I’ve been trying to get Sith Eternal Emporer for so long!