WOW ! so sad to hear of your loss
OP said 'right' side and am guessing driver's side.
Ford has had a history of driver's side fires from my RSS news feeds over the years
One is Cruise Control and other is MC PSI sensor leaks
IMHO & agree with your fire department, for a fire to get that hot that fast, must have started out as an electrical sourced fire. Then the other flammable stuff caught
Nothing you could have done if the hood latch was too hot to touch.
Also agree with comments to make sure it is fixed correctly, as this kind of fire could have compromised other subsystems/components that will be tough to find
Good luck with your insurance company.