Are you planning a summer vacation at all this year? Maybe you could change the plans & make them into a driving trip to California (although that's gonna be pretty expensive, too, this summer)
I think the best compromise is going to be to ask for either before or after the party (whichever is a greater length of time).
Your daughter shouldn't get to 'call the shots' in this, but her feelings & desires do need to be considered, too.
Do you have any time off coming up? Could you drive/fly out to spend time with her, there, in the week or two before the party?
