The inapp chat or even email@example.com will be your friend in this option. I asked about my friend who has no formal ID and this is the reply I got:
We have three verification processes in place:
Algorithm: we use a verification algorithm to help us verify your identity after you’ve signed up. It works in the majority of cases, but when it doesn’t work, we use in-app verification.
In-App Verification: With in-app verification, we ask you to send an image of an ID document, together with an image of your face, to check the resemblance, and verify your account.
Document checks: If the algorithm doesn’t work, and the in-app verification doesn’t work either, then we may resort to documents. This is the very last option, as it takes a lot longer to verify ID using this method, and it may require several documents.
In short it is very possible your friend will be automatically verified by our algorithm system, but if he is not, he can get in touch with us and we will provide him with a list of alternative documents he can send us - there’s always a way The documents we can accept are:
National Insurance number card
Benefits letter received from the government showing your name and address
Government pension entitlement letter showing your name and address
Council tax bill showing your name and address
Utility bill showing your name and address
P60 or P45
Bank statement from a high street bank on full letter head, showing your name and address
We will need to see at least one document from each group. I hope that helps, let me know if you have any questions!