Well, I tested both modules, and one of them turned out to be faulty. The other stick works, I can use my PC with it for now. And Corsair’s customer support turns out to be really handy; they can send a replacement first for a deposit, and after I receive it, I can send the faulty one back. And once they receive it, I can get the deposit back.
So it’s all (kinda) good now, regarding my PC.
I guess, any website served by Google Cloud wouldn’t work either.