I wouldn't be concerned.
They won't have simply not ordered the car I don't believe. You are the customer who has ordered a car, they will want to deliver it to you. If the sales exec says they've done it, then I'd believe them over what appears to be an unreliable tracking service!
My dealer held my order back for over a week. It was only because I hadn't received my order number that I chased (thanks to the feedback on this forum). Amazingly
, an hour later I had an order number. I also got the order date confirmed with VW Customer Services and it was NOT on the day they said they'd ordered it - in fact, its only because I chased them that the order was put through. So, for whatever reason, my order was held back. As soon as it was put through I had an order number, and that worked on the tracker the next day.
Not wishing to scare monger but if I would chase them. VW Customer Services said that you should have an order number within a few hours of the dealer putting that on the system - if you don't then they haven't placed the order.