> more resistant to heat considering the distance they have from the engines, in case something went wrong
For the engine to melt a window, something has gone wrong enough that this tolerance isn't material. (You'd need a lot of heat. Plus enough turbulence to blow it laterally inward, but not so much that it's allowed to cool. That combination suggests a loss of power and a low-speed, i.e. low-altitude, stall.)
From the article: "They located the source of the noise as a dislodged window pane aft of the over wing exit."
The engines are under the wing; the affected seals were over it.
If you're melting the window panes in this scenario from the engines, you're having a really, really bad day. Plus, the noise increase from a missing window pant would likely be the smallest of the warning signs.
For the engine to melt a window, something has gone wrong enough that this tolerance isn't material. (You'd need a lot of heat. Plus enough turbulence to blow it laterally inward, but not so much that it's allowed to cool. That combination suggests a loss of power and a low-speed, i.e. low-altitude, stall.)