Is this a MkII (1905) Ross? If so, the following applies. If not, the other models are different.
Don't drill it out. It's not stuck, it's captive. It pushes down through the bottom into the trigger pin bore in order to let you remove and install the ejector and spring, and the trigger pin holds it in place all other times. Push the trigger pin out and you'll see its bore. Then just tap it down from the top with a small punch to remove and install the ejector (it sounds like it shearing off probably took care of that for you), then tap it upward from the bottom to remove the pin when the ejector has been removed.
I might, I'll check and get back to you.
-Drew