I feed all of mine regardless of who is or isn't in shed. Most of mine will eat in any stage of shedding.
As for the rat, I would have left it in there for the snake to eat. Generally if they constrict it, even if they let go, they will usually eat it. They just need to be left in peace and not stared at. I have a couple that will unconstrict and leave it there if I bother the snake or close the tub.