Not working in 5.2 either. Seems they went on ahead and removed r.lumen.screenprobegather.screenspacebentnormal 0 preventing artists from being able to force this pass.
Update: r.lumen.screenprobegather.screenspacebentnormal 0 wasn’t removed but actually replaced with: r.Lumen.ScreenProbeGather.ShortRangeAO 0
Explained in the comment section of this video: How to use Lumen and Screen Space Ambient Occlusion (SSAO) in Unreal Engine 5. #ue5 #unrealengine5 - YouTube