Vise (2016). 4x5 Speed Graphic. HP5+ in R5 Monobath

There’s something wrong with my process or my equipment. I took this photo of a bench vise today using the Speed Graphic. It was lit using the Foldio, shot on HP5+ and processed in R5 Monobath from New55

I metered carefully, but it still ended up underexposed. What’s worse, is that the right one-third of the image is darker than the rest, and slightly discolored. I corrected for the coloration problem, but something is still wrong. I don’t trust the R5 developer. I’ll try again using D76 and see where I get.