“The water in the mixture defractionates out as a precipitate called condensation.”
I’m not sure that that step is needed. Could be just putting flame on the fresh mist will ignite it. I can’t try it right here, though.
I still doubt that this is really what happened. If it did, glycol/water fires in car crashes would be common, and fire departments would have a protocol for handling it.
Could be they are common but merely mistaken for more common oil fires.