I had a very similar experience but did not have the choice of where to pick up the vehicle. I had to call 8 times over the course of an hour to get someone on the phone. That person messed up the MVPA (ended up with credit) and my bank needed it changed and when I tried to call back I couldn't get anyone on the phone. Someone from another local delivery center actually helped me with the final details over the phone. Fortunately, I didn't have a trade in. I had an end of quarter delivery so I chalked it up to that but I'm guessing Buena Park is just like that. The weird thing was when I called the Tesla number and punched in my zip code I got forwarded to the Costa Mesa location where no one also picked up the phone and all voice mail boxes were full. It was frustrating but it all worked out in the end.
The delivery itself was uneventful. Show up, get pointed to where your car is parked, accept delivery on the phone, unlock, grab keys, drive off.