I looked up
duckduckgo.com/?q=dibond+aluminum+sheet. It's what I've known as Polymetal. Both are brand names.
Heat is right out. Explosive forming could work. Do you have a swimming pool?
Were it I, I'd prolly go for a low-poly faceted construction. It's less complex than this example:
Maybe one long dart to make a cone off-centered to the front and 2 or 3 at the rear to make a tearing edge/skeg. Lapping the seam might be possible, I've not had success with my experiments. a 3mm H-channel is another option.
My experiments:
Braking the flanges ruptured the outer skin. Scoring on the inside first might prevent that. I don't know about scoring dibond.