I thank God and Clay I was made aware of this problem with platine. As you have seen their QC is very erratic. Perhaps a light bath in oxalic acid 1% might remove the black spots and crap enough to allow you to use it for the 4x10 but I am not sure. From what I understand if you get the paper like that you are SOL.

I would suggest either do the oxalic acid bath, or just a plain water bath and see if some of the spots clear away. Good luck...