Not sure how that lock communicates. Probably Nest Thread (maybe someone can comment). It needs their bridge to connect to the outside world. I'm guessing your best bet with that lock is going to be what I did last night out of frustration with HomeKit for my August lock.
Don't fear the google cloud for reliability if you're shell shocked from owning that other hub.
I'm using this method for quite a lot with Google Assistant Relay and it's very reliable.
