A successful refeed usually shows up over the next few days, not immediately after the meal.
Things I'd look for to confirm success...
Better gym performance (strength, endurance, pumps). Fuller muscles and improved muscle roundness. Increased energy levels and reduced fatigue. Improved mood and less diet fatigue/cravings. Stable or decreasing weekly average weight after the temporary carb/water increase drops off. Reduced hunger compared to before the refeed.
Don't judge it by the scale the next morning. 500g of carbs can pull several pounds of water into the muscles along with glycogen, so a temporary weight spike is completely normal and expected.
The real test is whether your training, recovery, and adherence to the diet improve over the following week while fat loss continues at the expected rate.
If you come back stronger, fuller, more energized, and your weekly trend is still moving in the right direction, the refeed would appear successful.