Okay so what did he have over Levrone in 99 AC then that allowed him to overcome his apparent lack of muscularity and still win?
What did he have? Well he was giving the AC if you post pics, Levrone was clearly the better. Some say, that they punished Levrone for coming in lighter, others like Flex editor Peter M, said Levrone came in flat

. It was widely known that nobody knew which Levrone was going to show up, the lighter one or the FullBlown one. Or using your excuse, politics. Since Levrone already won it twice, it was time to give it to Nasser. But the consolation prize went to Levrone...as a wink and a nod. I don't know who votes on the MM award, possibly Arnold himself.
Just like Cormier losing to Cutler for 3 straight yrs at the Arnold, when he clearly was better.
Also to answer you Flex question, Flex has cross striations in his quads, one of the few bbers to have that. It adds a lot in terms of detail. In the Musclemag that featured the contest, the up close pics of Flex's quads are unreal.
Also, yes Nasser's rear lat spread is wider than Flex's, he was narrow. It is his small waist that gives him the illusion of width from the front.