Simple answer is that you just can’t do this. They will end up stomping on each other. Per device, there MUST be only one accessor.
If you need multiple-access to a device, you will need to create a thread or process that channels access through ONE instance of the API. Then all other threads/processes would communicate with that “FrontPanel Thread” for access to the device.
Two separate instances of the API bound to two separate devices cause no problem whatsoever.