I would have to 'fix' it too. It will need two pieces of hardened spring wire that are a couple of thousands less than the diameter of the cross pin. It will also need a very firm vise to hold the gun while driving out the old. The first piece is about 1" long. This is the starter drive pin. The second piece of drive wire should be about 1 1/2" long. It is the finisher after the S&W cross pin starts to drift out. Longer on the first drive pin and it is sure to bend while being driven. Also needed is a ballpeen hammer of 10 to 12 oz. weight with a like new driving surface on the head.
With the barrel firmly clamped in a padded vise put good light on the job. Hold the drive wire with a small set of vise-grip pliers. Make sure you and your arms are in a comfortable position. Make sure the drive wire is being held in near perfect line with the cross pin. Insert the drive wire and start out the stub. Change to the finish drive pin and complete the job. A little heat applied by a very hot hair dryer sometime helps.
BTW: Are you sure Bubba was driving OUT and not driving IN when this disaster happened? What can you see looking down the hole on the opposite side? There is a chance this was a barrel replacement with a barrel that did not have the small cross pin groove milled in-place. If so, you have a different problem than described above. Now, it becomes a precision drill press job with a carbide twist drill. Let us know.
Give me a chance to go out and back to my shop and I will give you the exact measurement of S&W's cross pins, but if anyone else has it right in front of them, please jump in. BTW No. 2.....the hardened drive pin wire is available at Hobby Shops. They call it model airplane landing gear wire. ....
Also, Brownell's has a drive pin set of wire gage, but they are too long as received and have to be shortened because if the drive pin is too long it WILL bend before starting to move the stubborn cross pin. PM me if you need further............
