That's a very fair question, IMO. Think it through a bit more and then consider...
If last instant Rwy changes are known common where you are headed, brief BOTH options before the approach. If different plates/routes/procedures are used, have BOTH handy and in mind. Always remember that as commander (or PF) on final, YOU are in charge. IF you can safely comply with ATC's REQUEST, do so and perhaps consider hand-flying the remainder, keeping eyes out. If ATC's Request simply comes too late to be safely flown, state that you are UNABLE, perhaps appending 'safety,' and continue the original approach (if a G/A becomes necessary, fly the original, published plan). And of course, to the greatest degree possible, try to keep ATC/tower informed of your intentions.
I'm sure that I've left out a couple of steps, but their are multiple variables here. If it must be said, again, you are responsible for the safety of your aircraft alone. That late in an approach, major changes from ATC/tower are requests, not orders. If all else fails, declare a G/A per the original approach and fly it. I know I'm probably missing something, but when an approach gets that snarky, fly, navigate and communicate seems to come to mind. At the very least, ATC will (should) understand what you are doing. You can shoot them later.
