Sometimes you just have to swallow hard and just get it done, for their benefit.
Today, I treated one of my hen's feet as she had terrible overgrowth of skin and scales post-mite infestation. She stopped eating and moving because they were so sore. I had to soak her feet and then pick off loads of hard scaley crud that was welded to her skin underneath. It was smelly and disgusting, and hard to differentiate between crud and skin, so she bled a little too. Poor thing, even her nails on some toes were covered with this thick overgrowth. Think the tree men in Bangladesh with the hard warts on their hands and feet. Anyway, she is much better now and resting in hen hospital with some special mash. Hopefully once they are all healed up in a day or two, she will be able to walk without pain.
Anyway, the point I am trying to make was that it was gross and tricky but had to be done. I couldn't let her die of starvation and in pain.
You can absolutely tackle the ascites draining. It is just a needle stuck gently in the right place. Get a helper if you can. Its totally doable.