633 Squad was actually used as temp footage placeholders for the space battles before the ILM comps were done, IIRC.
Kurtz confirms as much in an interview I'm using. But from there to it being a 'primary' influence... I don't know if I'm altogether convinced. I think you're probably right that it further ingrained the idea, and perhaps it even triggered the idea of fighters attacking the bombers, something that isn't present in Dambusters.