As has been previously discussed, the NEC does not specify ground pin orientation except for hospital installations. This was confirmed to me by my electrician (Master Electrician) who installed my 50 amp circuit and 14-50 receptacle. Given the short, often very short, power plug cord it makes sense to orient the receptacle in whatever position works best.jcanoe provided very helpful answers. To add to that, in case you also needed documented info from Tesla:
Circuit Breaker: 50 amps
Voltage: Single phase, 208-250 volt AC supply, 60 hertz
Four Wire Configuration: Line 1 - Line 2 - Ground - Neutral
Conductors: 6 AWG copper wire for circuits up to 150 feet
Outlet: Use a high quality, industrial grade outlet
Ground Pin Orientation: Top position of outlet
Ventilation: Not required
Example: The description of the Tesla Cable Organizer sold on the Tesla.com site has two photos that show the Tesla Mobile Connector w/ Chassis Holder mounted in two different orientations. It is not clear from the photo which power plug adapter is used in the photo but it is one of the larger plug adapters so probably NEMA 14-30 or 14-50. The same plug adapter appears in both photos so unless the ground pin orientation was changed to match the orientation of the power plug cord in one of the photos the power plug cord would have to be bent 180 degrees to align with the receptacle.
In the first photo the ground pin is in the conventional 12 O'clock position; in the second photo the ground pin is in the 6 O'clock position, else the power plug adapter cord would need to be bent 180 degrees.