I hope that they'll be able to report on the incident with some detail about the cause, if it can be determined, so the rest of us can be educated. There are certain fire risk issues in all RVs ... and I'm sure that Wanderlodges have their share of possibilities. It would be good for us to know what we all might watch out for so we can take appropriate maintenance precautions.

I've seen photos of a couple of wide body coaches that have had exhaust pipe fires -- caused by leaks in the exhaust system that runs up through the roof at the back of the coach. (Once started, the fiberglas end-cap will burn.) From the photos I've seen, the exhaust pipe fires didn't seem to have caused that much physical damage -- but the smoke damage inside the coach is usually very serious -- making a complete gutting and rebuild almost the only repair solution, if it's financially worth doing at all. The hint from those incidents it to carefully inspect the exhaust pipe/muffler for leaks as a regular part of maintenance. 

Another lesson is to ensure that the fire extinguishers on board are regularly inspected, replaced, or recharged. The common dry powder extinguishers eventually settle and compact (helped by the vibration in the coach), so become much less effective after a period of time. Even if unused, it's probably wise to replace them (or, if one of the better models, recharge them) every two or three years. CO2 or halon (or other gas) extinguishers don't have the same problem.

I note that I upgraded my in-coach extinguisher from a 2# model to a 5# model after inspecting the original, 11 year old extinguishers on board. I also replaced the 5# extinguisher located in the front, curb-side basement compartment. Costco had a reasonable price on replacement extinguishers.

I've long had good fire extinguishers in my home -- and I discovered that the 20 year-old extinguishers needed to be (expensively) pressure tested before they could be recharged. So, I simply replaced them -- I hadn't know about the settling/compacting problem until relatively recently. Try to get a model with all-metal valving, etc. Those with plastic parts are more subject to cracking and loss of pressure.