Just discovered this vlogger/thread the other day and I've been wathcing some of his old videos. The one he made about Enchantee may be the most out of touch review I've ever seen a vlogger give, and I watch the Dis Unplugged.
But to get to the point: this man is probably pushing 400 pounds. He's also only like 5'4, so he's probably pushing 70% body fat. It sounds insane, but it's probably true; he's probably carrying roughly 280 pounds of fat on him.
So, if you try to run at that weight, it's the same as trying to run with a 280 pound man on your back. It's a terrible idea. He's more likely to get injured than to actually run more than a minute or two.
I've done some personal training in the past and people who are that size and deluded to the point that they think they can perform an athletic feat like a 10k have no idea how bad things actually are for them. Based on this thread and what little I know about him, it seems like he's a "body positivity" type. It's great to love yourself and you shouldn't feel ashamed of your weight, but it's also a highly limiting factor in your life and something you can change dramatically without a ton of effort (at least at first).
If I were to work with Theme Park Express, I'd try to get him to WALK a mile before he RUNS one. Cut out sugar drinks and limit portions a little bit at a time. At his size he can probably lose about 2 pounds a week (or more) without making super drastic changes, and be half his size in 18 months. Then he probably could realistically run a 10k.
But of course that would mean cutting back on the cruising (or at least Marcelline Market), so probably not going to happen.