this email and even if you say that the telegram manager says it's not a scam. It's not something official. We will always have doubts. We can see in this thread that everyone says something and the opposite.
I suggest that Nucleus make a page on their official site to explain the KYC, the procedure to follow and so we'll know it's not a scam.
The way it's done: send all emails at once where we see the account of everyone, it's not serious.
Some people get e-mails asking for private keys or stuff like that, scammers pretending being Nucleus. Of course : scam.
But the kyc mail is legit.