Why the big secret?
My hunch is because she's an up and coming country singer and Pat's daughter, they're treating as a cute boon to have her come in to help out her father.
I too am disappointed. It really isn't worth the government top secret/signed NDA level of secrecy that seems to be around it.
Is she even doing country music anymore? Her Wikipedia page suggests she hasn't done much since 2013.
It makes more sense, as if it were a bigger star or a Wheel vet like Susan Stafford, they'd probably do more to promote it and sustain the publicity they got from Vanna's first couple weeks. While not a huge surprise for the game show community, I've seen the Wheel online community up in arms about way less than this, so maybe this is big for them.