Yes, if the muzzle blast contained sparks that could reach the pool of fumes in which the person was standing. Or if the pellets/shot/slug were made of a material that makes sparks when it hits something, that might ignite the flammable fume cloud. Ordinary gasoline has a flashpoint of approximately 45 degrees (F) below zero.
At any temperature above that, it puts off volatile fumes that can be easily ignited. Diesel, on the other hand, has a flashpoint well above room temperature (i.e. , around 125 degrees F).
As someone else mentioned, it won't ignite unless there is an adequate amount of air, but you didn't say the scene was underwater or otherwise devoid of excess air for combustion.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.