Thinking about this a little further, I think what Tesla is going to do will depend on how much money is given out, and the exact requirements.
For example:
If the requirement is that any EV be able to charge from any site, then obviously the easiest, and cheapest way is to pick up the phone, call Electrify America, EVGo, or whoever, and have them install a few of their chargers on the supercharger premises. Done.
If the requirement is that any EV be able to charge from any charging cabinet, then sell adapters.
If the requirement is that any EV be able to charge from any cabinet without having to purchase anything extra, then retrofit the pedestals, but then weigh that against how much $$$ they're taking in for that. It might not even be worth taking the $$$ if the cost is too high.
Does anyone know what the exact requirements are?