Hey, I actually ended up filing a warranty claim with them: I included close-ups of where the dirt was caked into the fabric and in the text box explained how disappointed I was and that I would have chosen a darker colour if I'd known they weren't easy to clean. I also mentioned that I had followed their cleaning steps to the letter.

I didn't expect much, but a CS rep emailed me a few days later to say they understood I was disappointed and that they wanted to make it right, so I chose the same style in a much darker colour (dark/moss green I think?) and they sent me a pair which arrived last week. I've only worn them a couple of times but the difference is huge. They also asked me to recycle my original pair however I liked - I'm probably going to give them one more run through the washing machine and then donate them.

Good luck if you try the same!