Oh no! I'm so sorry. I'm sending you some virtual hugs

I hate that for you.
Flystrike comes from flies landing on a bird, usually attracted to a wound or poopy butts, and lays eggs. In warmer climates the eggs can hatch within 24 hours. Once the larvae hatch, they begin to eat at the bird and can even create holes in the birds skin, possibly even crossing into the abdomen. These wounds attract more flies, which lay more eggs. It's really horrible. Treatment involves washing the wound and removing every single maggot. This has to be done on a regular basis (am & pm) until you don't find anymore. Then treating the wound left behind. Severity varies in each case. Oftentimes culling is the best thing for the bird. I hope this is the last time you see this on any of your birds, whether it's flystrike or not.