in my opinion the accidental flap instead of gear retraction alone does not explain it.
on the one hand it should be, even when it is of course bad airmanship and a dangerous situation , finally manageable by an experienced crew since the flaps and slats retract slowly while the reduced drag lets the plane acclerate quickly to its minimum clean speed. keep the nose slightly below stall angle, let the speed build up and then start to climb away. there were no obstacles ahead because they immediately were above the sea so no need to build up altitude at this moment .
on the other hand - even when not manageable - the "gear up" command comes shortly after liftoff and when the pilot instead of the gear lever operated the flap lever to "0" flaps resulting in a stall and crash it would have occoured in very close vivinity of the runway. i do not see a scenario where the plane struggels several miles out to the sea and even makes an u turn due to early flap retraction.