You have to submit actual real info including your national insurance number linking to your personal HMRC records. So it doesn't matter what your username is. Behind the scenes they gather the real details.I'm sure you can use any user name such as, The wolf. If you provide tiktok with the information they require and show identification then you can basically use any username, and your bank details will be linked and traced back to your tiktok account.
I've never used tiktok as a mean to make a quick buck but I'm sure that's how it works, someone on here might go live so they can correct me if I'm wrong as they'll know more than what I do.
Before, anyone could withdraw into a PayPal, bank etc. But now you're required to submit your NI details before you can withdraw (only once a year so that hmrc have a record)