They would normally have to do a debris analysis. I would expect them to burn up, because we'll have a real problem if Starlink satellites start surviving reentry. But it's possible that since this is a very low injection point and speeds will be lower that some parts might survive. If they do, it makes Starship survival look less impressive though...

They don't. Only very big or dense satellites will have anything reach the ground. Most burn up completely in the atmosphere.