Oh Honda. Any mod or accessories will void the warranty

If follow by the book this is not only limited to hybrid. All other cars also have this clause. Anything you change that is not authorised by SC will void warranty. However, it is not executed to the tee. Therefore, SC usually close one eye.

As for your hybrid of adding double lock. It should be fine. It's just that the acc shop dare not do the job as they are not experience enough. You could probably go to another acc shop that have experience with hybrids.

Not that simple for pedal lock as it will tap into the car electrical system. But yeah this is debatable.

BTW, if TS is still around, what is your FC like for the car?

I believe you can file a complain to KPDNHEP for voiding your warranty without appropriate reasons. And if your accessory does not touches the clauses that might cause warranty to void, I believe KPDNHEP will handle the case for you.

I once got a Proton SC saying my window run-channel rubber spoil because the tinted is too thick (whatever that means lol), then I report this to KPDNHEP, KPDNHEP give me a feedback letter, I bring the letter to Proton SC, and they let me claim the rubber.

Know your rights guys.