Hmm, that's not really clear enough to me to be able to say that it's definitely der... Based on the fact that it would be grammatically incorrect were that the case, I suppose the intended meaning is something else but it's just not enunciated clearly due to some combination of singing/slang/accent. Ok, it could be genitive plural... but that doesn't seem to fit the context of the preceding lyrics.
Flame is 'die Flamme' and they're conceptually different. Flame/Flamme is a regular noun, whereas fire/Feuer is abstract, like light/Licht, air/Luft, or nature/Nature. You can refer to fire as 'fire' or 'Feuer', without an article, for example 'Fire is hot'/'Feuer ist heiss', the same way you can say 'Light is bright'/'Licht ist hell'.
But you can't do this with Flamme. You have to say 'The flame is hot'/'Die Flamme ist heiss' or use the plural 'Flames are hot'/'Flammen sind heiss'. Thus, they're different things.
You could also approach the question ontologically and say that while fire is made of flames, a flame is an instance of fire, the same way traffic/Verkehr is made up of vehicles/Fahrzeuge, while a vehicle/ein Fahrzeug is an instance of traffic/Verkehr.