alt Hacker Newszero-knowledge proofs are a well-known tool in cryptography [1]. All Google is sharing is the library to implement it. Google would not have access to the information any more than they have access to the bank info of people who use Android or Gmail.
It's my understanding that they are sharing the library but they will also be involved as a facilitator, at least to the extent that people use their identity wallet service. It also seems like they will have access to who you are sharing information with, which seems like the most valuable information for a company in their position, with nothing but a pinky promise that it will not be tracked. Let me know if any of that is inaccurate.