Crispy pata is one of the few Filipino dishes where the skin is the main event, and pork skin fried until it shatters is about 550 calories per 100g. A whole front leg gives you around 800g of edible skin, fat and meat after frying, which is where the 2,200 plus figure comes from. Kawaling Pinoy's recipe card lands at 560 calories per serving when a leg is split 4 ways, and that matches what you get at a restaurant table.
The meat underneath is actually fine. Pork leg meat with the fat trimmed is about 180 calories per 100g, similar to a pork chop. The problem is that nobody eats it that way. A typical share is a piece of skin, the fat layer under it and the meat, and the ratio is roughly 30 percent skin, 30 percent fat, 40 percent meat. That is how 200g lands at 560 calories instead of 360.
A whole crispy pata costs 600 to 900 pesos in a restaurant and is usually eaten by 3 or 4 people with a platter of rice. Four people, one pata, one cup of rice each: about 820 calories per person. Two people finishing it, which happens, is about 1,100 calories each before rice. The soy-vinegar dip adds almost nothing, maybe 15 calories, so use as much as you like.