Let me try this analogy, maybe it will help.
Previously on the forum, someone passed fluorine gas though a hose and the hose caught on fire. Let us hypothetically add that the fire spread and burned down the laboratory. Let us also suppose if plastic tubing was used the same fire scenario would happen. Would you say that the hose or tubing caused the fire, I think not. Would you say the laboratory caused the fire, again I think not. What you would say is that fluorine gas caused the hose to catch on fire and that caused the laboratory to burn down. The reason is that it is a common denominator. Either the hose or the tubing would be set on fire by the fluorine.
No matter what the typical doping painted cover was made of, the Hindenburg would have burned rapidly due to hydrogen in the gas cells. It is likely that if the Hindenburg was filled with helium and somehow the outer cover was set fire, there would have been a good chance that the fire would be extinguished. If the gas cells were filled with just air, then it would have taken many hours to burn. Actually, long enough for crew to scamper topside and put out the fire. I would wager (purely educated guess) that if the cells were filled with oxygen it still would have taken a long time to burn. The Hindenburg burned entirely in 34 seconds and the hydrogen caused it.
As a postscript to the above the thought of doing burn test with oxygen is intriguing. One would have to set up the experiment very carefully and with protections.
Hopefully this makes things clearer. As was noted before, the papers cited by me address the IPT point by point and show it to be flawed.