I wouldn't have thought it would have fallen all the way to the sump, but if it has... Just a thought, if you jack up the front of the car as high as possible so the sump plug is pointing downwards, e.g. to the full height of your axle stands, then drain the oil, it might come out.
If it didn't, I would risk it and run the car anyway.
Or perhaps it will end up in the neck of the oil filter??!?!