The explanation I was given(and this well could be bullshit) was that they’re “sold”, in the sense that they’re claimed by a lot who will further sell them on, hence the storage on-property until they’re transported down the line.

Which is a very real thing for a typical auto manufacturer. Tesla, however, doesn't have any kind of third-party dealer network. They control the entire process all the way to the end-user.

Some are also held and leased for employee use, be it through employer vehicle loan or a leasing program like VW had, where you could select from a variety of models owned for the company fleet(including other manufacturers under their umbrella, like Audi) for up to a year.

This could be possible, not sure how Tesla operates.

That might work for VW but Tesla doesn't sell to dealerships. They're only available directly from Tesla. Which is also stupid. Hell, they have tried to sue owners of their cars for re-selling them.