Same as the design phase. It is guaranteed that engineers would have foreseen and been able to calculate the heat intensity.
They just didn't have enough influence or ownership of the problem.
Not the case. For the walkie talkie it was evaluated and the design (including location and it's orientation) were passed by a consultancy for a bunch of environmental items.
Seemingly that wasn't the case and they spent £13m retrofitting shutters. AFAIK the main contractor went after the consultancy for the money but I can't for the life of me find any references right now.