Gas smell inside the dryer

You might want to take a look at Dryer Smells Like Gas. There are also problems with the air gas mixture at the burner that can make a flame easier to blow out, a clogged gas orifice will make the mixture too lean and the flame will be unstable and can blow out and you will get raw gas flowing into the dryer until the flame sensor trips and shuts off the gas. It is possible in this case something has obstructed the orifice like a piece of lint also making an unstable flame with poor mixing. Also trying to run a dryer converted to LP on natural gas will have the same effect, LP orifices are smaller and operate at a higher pressure, and likely in that situation, the burner won't even ignite, or if it does it won't stay lit.