So you don't know anything about posing? For rear lat spread they lean back their upper body to make their back look wider. When you lean back, it also look shorter, and depending how much you lean, it look different. That's why they look like they have long legs and short backs.
You are a true "gum shoe."
Do a couple more examples to rule out kai leaning back. You can measure shoulder to hop height from the side n front too
He's definitely not the kind of guy to pick up 18 year old honeys at a club