I'm not an expert, but my initial reaction was "no." Just the size and weight of a pig next to a chicken feels really unsafe. It would seem they could get stepped on. But, I think you need to find a safer way to give your chickens more room. It could be a tragedy.
I also have a chicken yard covered all around with HWC with two coops inside. I don't close the doors to the coop, and some of my girls sleep on top of the coop. The HWC is strong enough to keep any predators outside. Been 10 years and no problems.
I'm so sorry. It doesn't sound like she is doing well. I understand you want everything you can to keep her alive, but you may have to let her go. Keep doing what you are doing and she if it makes a difference.