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Ask them? Most likely they'll want the keycard cuz Valet is very limiting can't open frunk, etc etc. And it'll drain your battery if sentry is on. If you're concerned the shop is gonna spoof your card, best to look at a different shop.
Speed limit mode (set in app or from screen). Or just don’t worry, they know you can track from app.
You could also signup for something like teslafi (1 month trial with referral) that would track the cars every move. There are many other similar products out there as well.
Just write down mileage and give them a card. If it’s a shop you justified spending thousands with they likely will not abuse your car. Don’t over think it.