I live 20 minutes from DLR, and have now stayed at the Villas twice. Once during the second week of operation, and again last week. On neither occasion did they try to charge me for parking, nor did they charge me the TOT up front. I had a normal hold placed on my CC, and the only thing charged to it by DLH was the TOT.
At VDH, you drive up to the guard gate, you tell them who you are, they give you a card for your dash with your name on it saying you are staying at the Villas, and they pull a ticket for you to open the gate. They do not take down your license plate number or anything else. When you leave, they look at your dash card, and open the gate for you. You don't even need to give them the ticket they pulled when you arrived, so there's zero possibility of them charging you up front. Also, because both were staycations, we had two cars going in and out every day. I asked the parking lot CM if I needed to keep the tickets they pulled to open the gate every time we came back, and was told I could just throw them away. All I needed was the dash card.
Conversely, at VGC, the parking charge ALWAYS appears on the bill, but is backed out at check out.