Well according to Brian Walsh of the NRSC they had confirmation from her staff because they had went all the way to the point of issuing press releases telling of her being selected to be the key note speaker. However Palin's staff later told the NRSC and the NRCC they could not commit the event to the governors calender until the end of the legislative season in Alaska. The NRSC and NRCC decided they weren't going to wait that long for her to officially commit and pulled in Gingrich.
NRSC: We would like to invite Sarah Palin to be the key speaker at the fund raiser.
Palin Staff: Oh that's WONDERFUL! She would be thrilled to do this!
NRSC: Great, we'll book it.
Palin Staff: Totally awesome!
Palin Staff after talking to Palin: Well can we get back with you on this after legislative session is over up here...kinda busy you know?
NRSC: Ummm...what?
Palin Staff: Yeah, we just need some time to make sure we can actually do this.
NRSC: Hang on a sec.
NRSC: You know on second thought, don't worry about it...you guys are obviously busy. We're gonna go a different direction so don't worry about being here.
Palin Staff: Oh, well okay...but hey, we never said we would actually be there.
NRSC: Yeah okay...hey gotta go, Newt is on the phone.
She didn't decline, she was disinvited. And it's not a good thing for her.
Guess who's not coming for dinner.