Just thought of this.....What would happen if you found the top of the pin, work the tip of the pin outside the table runner, get a wash rag or something put it on top of the top of the pin, and give it a nice hefty tap with a hammer. You will crush the top, be able to just pull the pin itself out and no one would be any the wiser. The top of the pin would be crushed and in teeny pieces. Anyhow, that's what I would do.
I TRIED IT! IT WORKS - IT REALLY DOES! The top of the pin with the "ball" on it flattens out and the pin, itself, slides right out. Son of a gun, I AM GOOD!!!!!!!!! The "ball" flattens out so nice, that you probably won't even know that it is in the runner. I tried slamming it on a table. Better off going outside and do it on the sidewalk or something concrete. Works like a charm. Hope it works for you. That is my 76th birthday present to you all who have a pin stuck in your work. Never too old to figure things out or learn, eh? Edie