Vanguard has warned its clients to make a copy of the check. Theirs are payable to the charity from the "IRA of ...." and sent to the taxpayer. The entire distribution will be on the 1099R, with no indication that a QCD was made, so I anticipate CP2000s down the road. The copy of the check might be the only proof.
Tell the local guy that with the new, higher, standard deduction, this is going to become a LOT more common. If he wants to keep his clients, he NEEDS to figure this out. It's not rocket science.