How can I prove the TPMS light did NOT turn on to alert me of low tire pressure?

What is your question?

After hitting a pothole I wondered if my tire was ok, but it seemed to drive ok and the TPMS light didn't turn on, so I continued driving. I got on the freeway about 5 minutes later and still no TPMS light. After a mile or two the car began pulling to the side, but still no TPMS light. I pulled over as soon as it was safe to do so, but my tire is now shredded and needs complete replacement. The TPMS light never came on at all! The dealer just wanted me to buy a new tire, but I'm pissed! I could've been killed because I relied on their faulty TPMS sensor and drove blindly onto the freeway with a damaged tire! Can the diagnostics prove that the TPMS never went on? I don't want to let the dealer brush me off if I can prove I'm right!! Thank you, :-)