I think I have an idea for who flamingos is. What is already known is -
Flamingo is DEFINITELY a YouTuber.
Flamingo is a girl.
I personally, think maybe Yammy? I am not sure, I do not know many YouTubers, but I know Yammy likes pink, and Flamingo is pink. I am not sure, but it is possible. Any other guesses? How about guesses for other masked singers?