Is the buyer trying to scam me? URGENT!!

I have a buyer( John) for my vehicle that I have listed on CarGurus. We have
met and taken a test drive and have  agreed on a price of $11300. The buyer
indicated that he had to get a loan from Langley Federal Credit Union in
Virginia Beach, VA, and that they needed a copy of the front and back of the
title for my vehicle in order that his bank would know what they are loaning him
the money for. I let him take a picture of my title( front and back) with his phone
after the test drive.
Then the next day  my wife and I received separate an emails  from Langley
Federal Credit Union ( outside of your system) indicating that they wanted my
wife and I to sign an electronic signature for a "Power of Attorney" for the
Virginia Department of Motor Vehicles.
I became very suspicious of this, and did not sign it. I told the buyer that I
wanted to deal in cash or check. If by cash, we would sign over the title at the
close of the in-person transaction, and give him a bill of sale and the two sets
of keys, however, if by check that I would deposit the check into my account
and wait for it to clear his bank before signing over the title, or giving him the
vehicle or the keys to it.

So here is my question:

Is what I have described strange in any way to your experts? I still have a
suspicion that I should not have let him take a photo of the title. What is your
opinion? If I made a mistake in this, what defensive move should I take at this
time?
Thank you.