Second, she should definitely go.
SPFGI has been the only strong invitational tournament for girls (was designed to pair with Denker), until USCF came up their own version: National Girls Invitational Tournament (NGIT) and US Girls Junior Closed three years ago. But SPFGI is still a very competitive tournament due to the participation of a few top girls from foreign countries and strong support from the Susan Polgar's Webster chess team. It's still a big honor and your daughter is representing your state.
Playing in SPFGI had been the dream for my daughter since she picked up the wood 10 years ago. We had qualified twice, but due to the mis-communication, we didn't know the first time and we gave up the second time because of some controversial issue. In 2012, she was invited out of blue (NJ is no longer supporting SPFGI), and finally fulfilled her dream to win the tournament. Therefore I have some experience to share.
Comparing to NGIT and Girls Junior Closed, SPFGI is a week-long activities. Your daughter's room and food are all covered. You only pay yours if you go with her. For older girls with no parent's accompany, the organizer will arrange pick-up from the airport. They will live in the student dorms, and eat at cafeteria.
The activities include two-day free camp, which helps girls bind with each other, one-day for sight-seeing, then puzzle solving competition and bughouse competition. After these is the 3-day 6-round tournament. Some GMs might drop by and say hello. At any time, you can find people play blitz or bughouse and have fun. You might end up playing bughouse with GMs.
Overall, it is a fun week. Your daughter will get to know lots of girls who are also playing chess and make many new friends. As a bonus, they have raised the scholarship to 100,000 and cash prize to 2,500 for the winner, which is higher than the other two.