Sorry, but that makes no sense, and the response from support in another thread makes no sense either.
It’s not the end device that starts a pairing request. It’s the hub. You have to start with the hub. That’s the “scanning for new devices“ step.Then You put the end device into pairing mode, and then it responds to which ever hub is sending out the scan.
As I said, I’ve had 4 z wave hubs operating in the same small house, no problem. (Two smartthings, one wink, one zipabox) They were all on different accounts, but end devices never got confused about which one they belonged to.
But more than that, there’s no problem with every unit in an apartment building having its own Z wave hub. Or even every room in a hotel, as the Wynn did in Las Vegas a few years ago.
Yes, there is a very small possibility that two people would be trying to add devices at the same time and they would accidentally connect an end device to the wrong hub, but it’s pretty rare and since the owner of that device would see that it hadn’t connected to their hub they will likely just reset it and try again.
So it’s just not a problem because it doesn’t work with the end device starting the process. The hub starts the process. All nearby Z wave devices hear that command. Only the end devices which are placed into pairing mode, typically by physical manipulation of that device, will respond.
As long as you don’t have one person in a household trying to add devices to, say, their ring alarm base station at the same time that another person in the house is trying to add devices to their smartthings hub, there’s no issue. Work with one hub at a time, and the devices will join to that hub.