That’s probably the case with others who have performed on The Masked Singer where the costume would’ve been difficult to sing through and into a handheld microphone.
For professional singers wondering how all that mic control worked out with a giant dinosaur snout in the way, it didn’t.
Using the handheld as a prop would prevent audience accusations of lip-syncing, or just give contestants something to do with their hands.
Jojo Siwa was merely holding a microphone, but actually singing through a headset attached to her face.