Your looking for a response that fits your logic of the situation. However, I as well as others, know that a bare metal roof on perlins have a 100% tendency to rain condensation inside the barn when the interior is warmer than the exterior of the building. It's not that the roof is leaking, it because your making condensation. Anytime warm air hits a cold metal roof, you have condensation and the suggesting of spray foam will fix that problem 100%.
Get a lot of ideas, then applying them to your situation. Trying to cut off discussion because you don't think that is "your" situation is not the idea of a forum. Yes, their is always going to be some noise in the discussion, but give it time and your solutions will unfold.