Here's one negative scanned as positive. The markings/blotches and fog are strongest on the area where negative is attached to quickload's flap.
However these blotches are everywhere. They're just much stronger on that area.
Yesterday I developed six sheets. Some of them have these markings, some are in perfect shape.
I did them in two batches. Three in D-76 1+1 and three in Pyrocat-HD 1:1:100. Similar results.