Oh Luciel, I can only imagine your frustration right now. It's the last thing that a bride needs. Did you get a group rate for the trip or is everyone expected to book on their own? I think maybe everyone is waiting for a last minute price as they tend to be cheaper. Either way you have done your part and now it's in the hands of everyone else. The most important ones will be there for you and your FI and that's all that matters. Sorry you are going through this. This is my biggest fear!
I know with our wedding a deposit is going to be due 6 months prior to the wedding with the remaining amount due 2 months the big day.
Everything will turn out for you!!!! Don't stress about the small stuff. Either way it's your day and if your FI shows up that's all that really matters