If by scientists, you mean like 5.....
Abiogenic oil theory still has never gained any real support, and has floundered as the refuge mainly of those who try to refute dinosaurs and support creationism because the billion year creation model of the earth tends to go against their beliefs...
It has never actually been able to successfully find commerical oil, and fails on numerous levels...
Peroleum Geologists still ad hear to the rotting dino oil theory overwhelmingly..
Including big oil companies..
In regards to the gulf of mexico oil... The easiest way to visualize it, is consider the super continent Pangea; the combined super continent that split up about 200 million years ago...
Basically all of that area was dense rain forest for a significant period of time... so ~ 50 million years of plant and animal deposition and build up getting swallowed by plate tectonics, then heat and pressure doing their magic...
This is also why that area tends to be rich in other minerals and that upper horn on south america is heavily mined...