Not responding to your whole post, but it's a hell of a lot easier to make your own leak, than it is to edit the banner in a believable way.
The Rayman Leak doesn't involve anything more than the already available and released CSS from Smash 4, which was used, and literally his art render of Rayman. That's it. That's literally it.
This banner has, on art alone:
- 7 unique art assets not found anywhere else
- All 7 fit into the odd artstyle the banner has, from what we can see
- All 7 are seamlessly added to the banner, but displace nearly all of the characters around them, who further displace every other character around them, like a ripple effect. There are hundreds of these changes all over the banner, and this has been verified by many other people.
- Many displaced characters revealed new art, and moved several characters to completely different locations in the end.
I'm not saying it's impossible, but even professional photoshoppers can't replicate it. We had one on Reddit, and after 10 hours he had to stop because he could not grasp it being fake. He himself had too many glaring flaws. You need actual assets to move these characters seamlessly across the banner. Additionally, there's also the question of why the leaker would ever spend the time doing all of those minute, subtle changes when all he was doing was faking it for fun.
In addition to all the things you say could just be rused, not to mention the insanity that the supposed fake leaker would have to express for doing such a thing like impersonating an employee, which is highly ****ing illegal.