"Yes.
Lin Yuan also watched the program. Based on his understanding of the singers he collaborated with before, he knew the identity of the performer named Fishman almost immediately after listening to his singing:
Sun Yaohuo!
Senior Yao Huo indeed altered his voice line. This alteration was enough to conceal his true identity. However, Lin Yuan had collaborated with Sun Yaohuo on so many songs that it was normal for him to guess it out.
As for people like Chen Zhiyu...
Lin Yuan could only make an approximate guess. He couldn't fully confirm, so he held a half-doubtful attitude when he saw comments from a netizen named Little Dinosaur Loves Fish.
However, when the other party pointed out that the mermaid might be Jiang Kui, Lin Yuan agreed quite much.
He had suspicions before.
So it might be a coincidence. Many singers he knew also participated in The Masked Singer!
However...
