He has a hundred shadow defence no matter what. You'll need max UVs and stuff to actually make it significant. Still, the difference between minimum defence (100) and a proper set like say, Snarby (about 140) is a pip's difference so it could be the difference between life and death. The main loss of defensive capability in your set lies in the lack of a penta (six pips less than "normal") as well as just having an Ash Tail piece (one pip less than Skolver). Don't be too sure he had no DI, either. He may have had trinkets which could've given that increase.