Oh, and I should add I’m sorry that the avenue you took didn’t work out. Maybe not all is lost.
Keep in mind just because the tyre manufacturer says the tyre vibrations are within their margins, it doesn’t mean the average punter would think such vibrations are also ok. Many an average punter may feel there is a defect somewhere in the vehicle (which is the product you bought after all, you didn’t buy the tyres separately).
Also, the vehicle maker may have a differing view on the overall quality of their product as a whole, than the component tyre supplier. This may be due to the vehicle maker seeing their product living higher up the market sector (their product is the whole car not a tyre). As such they may have already costed some warranty for out of spec tyres... who knows...
I still feel that knowing your statutory warranty rights and going to the vehicle seller is often a better approach. Yeah, I know others have a differing view but in this case it seems the horse bit you rather than getting it straight
No disrespect meant
Hopefully you still have the energy to deal with this, otherwise just buy a new set of pirellies or anything other than Bridgestone and be done with it.