Sponsor signature form?

I've posted this in the 'Ask Student Finance' forum but thought I'd ask here too in case I can get a faster answer.
I'm applying for student finance for the first time, and my dad got an e-mail saying;

"We are still unable to progress with their application(s) for the following reason:

Sponsor 1 signature missing
Please complete and return a Sponsor Signature Form to ensure they are assessed for their full entitlement to student finance. You can download a Sponsor Signature Form at www.direct.gov.uk/studentfinance."

I've looked on the website and can't find a Sponsor Signature Form, so I've not idea what they're wanting really. Is it the declaration page from the PFF2 form? Though I'm pretty sure that was signed, obviously I can print it off and resend it.
Help please!
Ellie

His signature