It sounds like you're confused about what was said, but the OP seems to be a bit confused, too. The OP simply said that after generating over 2 billion random combinations he didnt find one particular combination. It's entirely possible to generate 2 or 3 billion combinations and not match a particular combination, because there's no guarantee that you'll generate 100% of the possible combinations.
As far as what the OP actually meant, it sounds to me like he thinks he generated a set of 65,536 combinations 32,767 different times, and the 2 billion random numbers means 2 billion randomly generated combinations. That's why I'm sure the OP is confused. It's extremely unlikely that his program is doing what he thinks it's doing. Each set of 65,536 combinations would have roughly a 1.7% chance of matching the combination he was looking for. That means there's a 98.3% chance it won't match. Doing it 10, 20 or 30 times, it's still unlikely that he'd get the match he was looking for. Doing it 32,797 times, OTOH, it's incredibly unlikely that he wouldn't get the match. As he said, it should have been expected about 562 times. In fact, all 3,819,816 would have been expected an average of 562 times. Many of the combinations would have turned up more than 562 times, and it's certainly possible that one of the combinations wouldn't have shown up at all, but it's exceedingly unlikely that a particular combination wouldn't turn up even once. It's literally trillions and trillions and trillions and trillions more likely that Excel is working properly, but simply not doing what he thinks it's doing.
Without being familiar with Excel programming I'm just guessing, but I suspect he searched the same set of 65,536 combinations 32,767 times. He was looking in the right lake, but he only looked at the same 1.7% of the lake over and over and over.