Talking to MTV News, Reinhart - who was a finalist on American Idol's tenth season - shared her thoughts on Carey, who she branded an "amazing diva".
"I think it's a great choice, and I don't think they could have done much better than that," Reinhart explained.
"She's a huge diva with a huge, beautiful, amazing voice. I don't think that there's anybody who could give better critiques to people who are trying to be aspiring singers, so I think they did really good."
Reinhart added that she is glad Carey was not a judge on her own season, adding: "I think it would be a little more pressure. So I'm glad she wasn't there, but it would have been very cool to meet her."