not sure about the bottom, but if the crop (throat) area is squishy, it may be sour crop. do a search, tons of information. I would wait until tommorow morning and check their crops before they eat. if it is still squishy and full that may be just what it is.
Is the bare spot on the breast bone? Birds actually balance on their breast bone when they roost so you may need to check and make sure the roost is wide enough, I think 2x2 is standard, someone may be able to correct me on that one. Also, if a bird is going broody they will pull feathers when sitting on eggs, something about keeping the egg close to skin? Just some thoughts, please BYC correct me if I am wrong.
My girl had sour crop and it felt like a water balloon. it also smelled a little like sour milk after a few days with it. I seperated her into a dog crate and with held food for 24 hrs only giving her access to apple cider vinegar water (the raw unfiltered kind - Braggs is a good brand) to kill off any bacteria that was forming. on day two I gave her yogurt to get the good bacteria back in her crop, then for a few days after that just soft foods, scrambled eggs, oatmeal. everyday I would massage her crop to get whatever was stuck in there moving.
She is all better now, but it took a while.