Get Daedric Armor
Instead of killing the man you need to finish the story in Tel Fyr, just get his armor in these various locations.
Daedric Cuirass- Found either by doing Mistress Therana's quest in Great House Telvanni or in the Wailingdelve, so use a torch because its hard to see in the dark. The Wailingdelve can be found in the Citidel of Myn Dhrur, in the Daedric Ruin, Hidden in the Dwemer ruin in the Plaza Brindisi Dorum for the story.
Daedric Face of God- Found in Sepulcher, with the Stormkiss, except for the Daedric Face of God, you need to levitate at the beginning to where the crystals are.
Daedric Face of Terror- Found on Enar Dralor in Ghostgate, Tower of Dusk, Lower level in glass armor.
Daedric Face of Inspiration- Found in either Mamaea with the fang of Fang of Haynekhtnamet, found in Ibar Dad with the Eildon's Ward and on a Buoyant Armiger in the top level of the Tower of Dusk.
Daedric Gauntlet (L)- Found in Kogoruhn, Charma's Breath, or the Black Heart (one of those)
Daedric Gauntlet(R)- Either kill the Imperial in Aryon's Chambers in Tel Vos or found with the Daedric Gauntlet (L).
Daedric Pauldron (L)- Found in Karstaag Tower, Solstheim. It's the top spire on top of castle Karstaag. Inside, the pauldron is nearly invisible in a crack.
Daedric Pauldron(R)- Found in the Wailingdelve, just sitting on the rocks.
Daedric Greaves- Found in Dren Plantation on the shelf in Dren's Villa or do Mistress Therana's quest.
Daedric Boots- Found on a shelf in Galom Deus.
Daedric Shield- Found randomly on Golden Saints, found on a man in Dren's Villa, Dren Plantation.
Daedric Tower Shield- Found on Golden Saints.