So, effectively, no you cannot cut this bot off.
To make it worse, the bot doesn't always follow the same pattern. Sometimes slightly different names, addresses, etc.
We initially thought it was fraud attempts, but none of them actually attempt a checkout. They just enter all their info on the checkout page, get the final quote, and bail.
It would have been nice if Google told people about this instead of it just happening. Or allowed you to schedule a time slot for it to do what it's going to do.