It's impossible to know how he died

He was on fire for a little while, and then I made him go downstairs and he ran into a million zombies. (Okay, maybe not a million.) And then he died.

Why weren't THEY set on fire when they started eating him? Or, I don't know, when they walked INTO THE FLAMES?

I am not a PC gamer, these controls are killing me. Either they have to let me change them around a bit, or they have to make it so you can use a gamepad. I'm going to keep dying.