I doubt it. When my father and I went not too long ago, everyone was just walking by, and some barely even glancing at its direction (this was after early entry). But a few people took photos and walked away, while some did question about the ride opening. However, there wasn't a ton waiting and wondering if it was opening like my father and I were. Finally, they noticed us waiting and told us about what was going on and to came back at a certain time (which we did, as instructed).
So, I doubt first thing in the morning "5,000 other people" will be there. It might be a little more since it seems closer to it being official and they are opening it now in the morning, but I doubt there is going to be a flood of people waiting and watching, especially during early entry. They will be too busy focusing on going to Hogsmeade more than likely. Even after early entry, that typically seems a lot of people's focus is going to the Harry Potter sections of the park (whether it's IoA, or USF).