It’s not possible for them to add data to your website.
They are a search engine. People pay tons of money to make sure their web site shows up in search engines... and then Google tilts the board.
That sounds like legal fight to me.
Yes I know they don’t add code to your files- but they might just as well have- given how the internet works to the outside world containing your customers.
I can see a legal eagle making a convincing argument of that to a jury of ‘gibmedat’ types