The bottom of the car is plastered in plastic panels. They're relatively easy to remove. It's really not a big deal if it's down there. Just let nature do its thing and let it fly out. All sorta of debris ends up there.
I mean, this is small enough where you might be able to claim it was never there. Warranty should be fine. They're not going to come after you because a clip is missing. That said, they will be able to detect you had a JB4 in, so there's that as well. (acceleration watermarks, etc).
Ahh - for the sensor clip replacement, you're going to need to do soldering, or replacing a large amount of the harness. I'd probably skip that in your case.
The metal retaining clip is either this or this.
I'll find the sensor clip in a few minutes, but you likely don't need it. A zip tie or electrician's tape will almost certainly suffice.
I could possibly see a world where Toyota of Orlando has a deal with Titan to order a new motor at cost or something, but this isn't how warranties work. Typically the dealer makes a request to corporate, corporate does their poking around and approves or denies. Dealers have some pull on the...
This part is definitely not true, the rest is spot on. The brake thing is massively expensive, is incredibly dangerous, and affects ALL BMWs, 99.9% of which aren't tuned. This isn't a back door to our ECUs, it's a legitimate safety concern.