Two people rent property only one tenant on AST?

Tax Planning and Financial

I have two people wanting to rent a flat, one applicant will pass referencing with flying colours and is willing to take responsibility for the whole rent and bills, while the other can only prove he is employed and being paid, his wages are paid into a friends bank account. he has a NI number but no ID as such, or any credit.

Can I grant an AST to both tenants or to only the one who is going to pay the rent etc.
How should I deal with this situation or should I avoid it at all costs.

Your advice is much appreciated

Kind Regards

Richard Thorne