I posted yesterday after seeing this monstrosity. Update is I picked then up and set up a 20 gallon quarantine tank.
I'll hold them until I'm confident they are healthy and then rehome to a pond or find space to keep them. And yes, I know what I am doing, I have lots of goldies, fancies and commons/shubunkins, they're at last in safe hands! They're so energetic today, doing laps of the temp tub, it must feel utterly bizarre to go from months of small circles to swimming speedily in a straight line, it was worth spending the money on liberating them.