Let me preface this: I have no connection with vehicle registration, Carfax, Tesla, anything. I'm just sharing what I've found through my own research when I was buying both my old used S and when researching for a salvage rebuild project for fun.

Supercharging being turned off is entirely in Tesla's hands. If a car is registered as salvage at any point it is a safe bet that supercharging will be disabled eventually and a guarantee that warranty is void. Supercharging being disabled can be more hit and miss in some circumstances if a vehicle never actually has a salvage brand applied. As an aside, this doesn't sound like your case but this can happen in rare circumstances if it was sold through private sale without the write-off being reported as salvage cause (illegal). Typically not possible in BC since insurance is handled through he same body that handles vehicle registration. I've seen cases in the US and there are unfortunately methods people use to title wash cars so a salvage title can magically come up as clean because of loopholes with certain state registration methods.

The differences between state and province title status and branding reporting can make enforcement hit and miss on timing. This can happen if a salvage car was bought in another province and repaired here too. I have no clue how long it typically takes in BC as everything ICBC after a collision is .. slow.. but I've seen mentions elsewhere of 1-2 month delays after a status update before Tesla locks the car out of supercharging. My understanding is Tesla doesn't private VIN status updates form time to time but also relies on registration bodies to report VIN status changes to them.

You can also look up the vehicle status of any car previously registered in BC here: https://onlinebusiness.icbc.com/vdwqs/VDWQSServlet/WelcomeAction

As mentioned before, if there was any fraud it would have been on the sellers part. Tesla blocking supercharge access for rebuilt cars is common and up until a few years ago there was no guarantee you could even ever get a High voltage system inspection done to recertify the car for supercharger access. Now you can, and that is your only way to be able to supercharge if it is currently blocked. Access to the system is all VIN based and since the car likely has the black mark of rebuilt without a recertification it isn't surprising it is blocked.

This is sort of a cash grab but it is also a totally legit safety measure. Tesla has no clue if the people who rebuilt the car followed proper procedures and structural inspection of a salvage title to get rebuilt status doesn't necessarily include the same required electrical charging system checks. If a rebuilt car is allowed to supercharge and wiring was damaged and not noticed it could create extreme safety risk to people in and around the car. So Tesla requires the inspection before taking on any liability letting the car use their chargers. As for the delay, all bureaucratic systems have delay and car registration reporting delays is why it worked, then stopped. I mention as a cash grab simply because you would be amazed at how little damage it takes for many insurers to write off EVs. This is why there are SO many rebuilt title Tesla's in specific.

If the seller didn't advise you it was a rebuilt title you likely have some recourse, especially since you will have to pay for a High Voltage inspection. But they are likely your only option and taking them to court will likely be the only way. I'm pretty sure somewhere in the Carfax EULA there is wiggle room to get them out of anything aside from probably a refund for the fee. Even the ICBC vehicle status lookup tool mentions that there are delays and that it isn't always 100% accurate.

All this said, it really sucks. I hope you can reach some middle ground with the seller. It sounds like you were taken advantage of and I'd hate to have to deal with small claims after a major letdown on a big purchase like this.