JayUtah
Penultimate Amazing
It is absolutely reasonable, as you claimed to have the appropriate understanding.Simply demanding I provide settings off the hoof is not reasonable.
What were the camera settings you used to take photos of stars that you claimed confirmed Marcus Allen's expectations? You already admitted it would take something like a 15-second shutter speed to expose stars. Did you use a 15-second shutter speed, or did you use one on the order of 1/125, which is what it takes to photograph a sunlit scene at that ISO and f-stop?
These are simple questions any remotely competent photographer can answer. You're not being ill-used.