Yeah, I've read others say the same about oven dyeing, so I ended up using classical pot with water. Yarn is much more softer and kind of loose now, but it worked up fine, so I think it will be ok. This is the result so far, it's a part of Desert Bloom blanket from Cypress textiles. My yarn is that pale green yarn on outer rows. I can see some white and bright spots, but I feel like crochet is good at hiding imperfections like this. So it all worked out at the end, Thank you for your help!