Conquered Virindi tells you, "Yes, I still obey the Master. Please. If you have the Glowing Virindi Cloak, I will take it in exchange for the Singularity Mace. Please. If you have a Singularity Mace, let me enhance it for you. Please?"
You give Conquered Virindi Glowing Mosswart Shroud.
Conquered Virindi gives you Singularity Mace.