630 calories for a plate of grilled beef is honestly pretty reasonable, bro. You are getting 50g of protein out of it, which is solid. The issue is the fat, 38g, and that comes entirely from the beef cut. Batang pinang and brisket have decent fat marbling, and when it gets grilled and then soaked in a kicap manis marinade with brown sugar, those calories stack up fast. The dipping sauce is basically nothing calorie-wise, 40 calories for 30g of chilli-soy-lime, so do not stress about it. Worth flagging that these numbers are a ballpark estimate because there is very little hard calorie data published specifically for this dish, so treat 630 as a reasonable working figure, not a precise lab reading.
What actually moves the number is the cut of beef and how big the portion is. If the uncle uses a fattier brisket or gives you a generous 300g plate, you are looking at closer to 850 calories. Swap to a leaner cut like tenderloin with a lighter marinade and you drop to around 480. The marinade itself adds about 50 calories from the oyster sauce, kicap manis and sugar absorbed into the meat, so asking for less marinade or a drier grill does help a bit. Paired with plain rice this becomes a complete meal, but watch the rice portion because that is where most people accidentally eat another 300-400 calories without thinking lah.