From the testimony I just read, there are no stains on the waistband. This is from Fassbender's testimony on page 174-175
https://drive.google.com/file/d/0B9dpNu3jLO3tMENkSjlRME5ROHc/view
A Yes. Urn, white stains on the lower right-hand pocket area of the blue jeans, and also on the upper, uh, left-hand pocket area of the blue jeans there's some white staining.
Q. Some stains around the, uh, bottom portions or around the knees as well?
A. Yes. Spots and stains that are white.
JMO but this seems quite consistent with standing on the garage floor... pouring bleach on the stain, of course it's going to splash up. Even if he uses his feet to wipe it with the rag (that he said came from a bag of old clothes that don't fit him or his brothers anymore), how does the rag get to the fire. Like he testifies too..... he picked them up... with his fingers (page 35
https://drive.google.com/file/d/0B9dpNu3jLO3tZk1VTkk5YmhfbHc/view )... and put it in the fire. The description of the stains are consistent with a 15 yr old kid that puts his hand in his pocket and/or wipes his hands on his jeans because his hands are wet/dirty after picking up the rag.
My source for this is.... I'm a mother of 3 children, and 2 step children. If I had a nickel for every time I saw one of them wipe their hands on their pants, I would be rich and sitting on the beach right now! I agree Sinsaint, he probably washed them himself that night and put them away so that Barb didn't see them.
I did look for a picture of the jeans but was unable to find one. I found many of pink fluffy handcuffs though while searching.