>>>is this fraud?
It's 'fraud by misrepresentation', contrary to Section 2 of the Fraud Act 2006:
http://www.legislation.gov.uk/ukpga/2006/35/section/2
>>>could bailiffs call over his debts
Bailiffs can only become involved after:
a) the debtor has failed to meet demands for payment ; and
b) a County Court Judgement has been issued against the debtor ; and
c) the debtor has failed to comply with that CCJ ; and
d) the lender has then obtained an enforcement order, permitting the use of bailiffs, from the County Court.
Further, they can only take property which is owned by the debtor, not that which is owned by someone else living at the same address. So there's no immediate worry about bailiffs turning up on your doorstep but you could well see debt collectors (without bailiffs' powers) arriving at any time, which would at least give you the opportunity to explain the situation.
Your first course of action should be to file a 'Notice of Disassociation' with each of the three main credit agencies. Write to
Equifax Credit File Advice Centre
P.O. Box 1140
Bradford
BD1 5US
or phone 0843 515 8357
to ask for a form.
Experian's form is available online (although you have to print it out and submit it by post):
http://www.experian.co.uk/downloads/consumer/financialconnections.pdf
CallCredit also offers a similar way of doing things:
www.callcredit.co.uk/files/Disassociation%20Form%20v2.0.pdf
Then have a word with your local Community Constable.