The wrapper is the problem, not the filling. Before frying, a 45g cha gio is about 70 calories: 10g of rice paper or wheat skin at 35, 15g of pork and prawn mince at 35, and a spoon of taro, carrot and glass noodles at 15. Then it goes into the oil for 4 to 5 minutes and the wrapper drinks up 4 to 5g of it, which is 40 to 45 calories per roll. That is how you get to 110 to 115, and the NIN figure of 230 per 100g says the same thing. A double fried roll from a cart that keeps them warm in the oil is closer to 135.
Nobody eats one. The normal order is a plate of 4 to 6, so 460 to 690 before the sauce, and the nuoc cham bowl is another 20 if you finish it. Where cha gio really adds up is as a topping: one on your bun thit nuong takes a 480 bowl to 620, two takes it to 750. At a bia hoi table a plate of 6 nem ran with 2 beers is 1,000 calories and it is only the starter.
Filling changes less than people expect. Cha gio tom (prawn) is the lightest at around 85 per roll because prawn is lean. Cha gio chay with mung bean and mushroom sounds healthy but the NIN table lists it at 130 per 100g before frying, and once fried it lands at 100 to 110, the same as pork. Cha gio re, the lacy net wrapper version, soaks up the most oil and runs 140 to 150 each. Size matters more than filling: a fat Saigon roll can be 60g and 150 calories.