T-Rex is a YouTube star and most of 'The Masked Singer' panel knew it

LOS ANGELES - Ken Jeong and Will Arnett didn't know who's been performing in the T-Rex costume, but Nicole Scherzinger, Jenny McCarthy-Wahlberg and Robin Thicke sure did.

On Wednesday night's episode of "The Masked Singer," T-Rex revealed herself to be the popular singer and YouTube personality JoJo Siwa.

"Once Jenny started saying a whole bunch of stuff, what happen was, she made it so clear," Siwa explained in her exit interview. "And then Nicole came in and helped with the clues. And, I mean, it was just a whole thing."

T-Rex performed “Jai Ho! (You Are My Destiny)” by A.R. Rahman and the Pussycat Dolls. Scherzinger actually co-wrote the song as a member of the group.

In past weeks, T-Rex performed Salt-N-Pepa's "Push It" and “So What” by Pink.

Siwa's clues included a boomerang, a nod to her debut single of the same name.

He coach said T-Rex "subscribes" to the idea that there is no day off. That made Scherzinger think of YouTube.

Siwa said she had a blast with the show, but noted, "keeping a secret is very hard." Siwa found it difficult not being allowed to talk to anyone, even the crew members she recognized.

"The dancers can't even know who I am, and one of the dancers is actually, like, one of my good friends," Siwa said. "She danced for me for, like, a year and a half straight. And I was just like, oh, I just want to tell you so bad that it's me because I just want to be friends here and hang out."

T-Rex was the final member of Group C to be sent home. The remaining contestants from Groups A, B and C form the Super 9.

They will face of on April 1 on FOX.

This station is owned by the FOX Corporation. This story was reported from Atlanta.