I think he & his team are the people furnishing the numbers. Seriously I don't think he has a snowball's chance in Hell but I hope he can do it.
His chances are excellent. Most people don't know that most professional athletes hold wrestlers in awe due to their commitment to year-round schedules and fitness and the fact that most must work through their injuries.
Brock has an extra advantage by being one of the fittest wrestlers who ever lived with relatively little damage to show for it. He proved his intelligence and physical control by putting on hundreds of entertaining matches without seriously harming anyone (guys his size are notorious for "working stiff").
Best of all, Lesner left the WWE in good graces knowing that he may have to fall back on wrestling. Pretty wise for a 26-year old.