I have no doubt what he has done is real, and I bet It is even impressive on many levels, but all structures can burn, even concrete ones. The people of Black Forest, a neighborhood just a few miles from my own forested neighborhood, are not stupid. They did plenty of fire mitigation, but when you live in a State that hovers at 5% humidity for weeks on end and less than rain than most deserts, fire has an easy target.
Black Forest, CO, gets 19 inches of rain per year. The US average is 37. Snowfall is 86 inches.
http://www.bestplaces.net/climate/city/colorado/black_forest