Since we do not know the causes of DOMS (delayed onset muscle soreness), we can't say whether Yin Yoga will help you or hinder you. What you can do is test it out for yourself.
The old theories about delayed onset muscle soreness centred around lactic acid build up in the tissues, but that is no longer believed to be the cause of soreness. Today we believe that the soreness is a result of micro-tears in the muscle, which may actually be a good thing: it stimulates the body to heal the muscle, and while the muscle heals, growth hormones and other factors are released that help other tissues (such as our organs) also grow healthier. There is still debate over whether we need to have this post exercise achiness or not. You will have to decide whether your work outs are too strong, or just right.
What can be done once you have the achiness? Should you do yoga? A study done in 2014 (The effects of yoga training and a single bout of yoga on delayed onset muscle soreness in the lower extremity
) found that doing yoga after exercises that lead to DOMS helps reduce pain and increases recovery time.
The type of yoga might make a difference, however, so will this work for you? I don't know ... you will have to try it and see, paying careful attention to the sensations arising. Of course if the pain increases, stop and remember this for next time. Personally, I would certainly investigate the possibility that Yin Yoga could help me with DOMS, but I would be gentle and would not hold the poses too long the first time I tried this.
Remember, Yin Yoga does not generally target the muscles, but rather the fascia and connective tissues. Yang forms of yoga do target the muscles, and since the study used yang yoga, if that was okay for the muscles, I suspect Yin Yoga will be too.
If you do try it, please let us know how it goes!