Ah, I missed this one earlier.
Now..... you report this metallurgy professor as stating that the steel bow visor had been exposed to temperatures higher than 1600 degrees. And since the professor is in Norway, and since every interested party is in Europe, it's not a stretch to assume that the temperature he's quoting is in Celsius.
But....
Steel melts at between 1400 and 1550 degrees Celsius (depending on the precise type of steel).
So is the professor claiming that he's seen evidence of parts of the steel visor having melted then re-hardened? (And even a flash exposure to that temperature would have caused melting, owing to steel's low specific heat capacity (which means it does not take much externally-applied cumulative heat energy to raise the temperature of the steel quickly and to a greater extent))
ETA: Ah, I see that as I was writing my post, you added in an erratum on the reported temperature (incidentally, and without me having to plough through the primary source material, was the error made by you, or by the "Focus Group", or by the professor?)