Answer:
There is no official form, but there are several out on the web, such as this one:
http://www.tdhca.state.tx.us/ocidocs/forms/09-RentMtgVerification.pdf
I'm sure you could use it as a template to develop your own. I would suggest that you have the applicant sign the form giving the current lender authorization to release the information. Whether the current lender will cooperate is another question.
First published on BankersOnline.com 3/18/13