It's likely in the pan, but you gotta find it. Is the set screw magnetic? (test the other one), if so, drag some magnets across the pan bottom.
You can try to pull the timing cover and see if you can fish it from the front
You can try to pull the timing cover and see if you can fish it from the front
It looks like the bay of a Customline we did a sbf in awhile back. Different car of course.
My fear would have been the off chance it doesn't make it down to the oil pan and somehow ends up staying in the rotating assembly and jamming somewhere..... catastrophically.
Once in the pan, i agree the screen on the pickup would have caught it.