This isn’t an ‘officially supported’ way but @AndyRawson has posted a solution here
You’d need to change
https://graph.api.smartthings.com/account/list
To
https://graph-eu01-euwest1.api.smartthings.com/account/list
When you’ve done that you should be able to select which contact the push notification is sent to in the smartapp/rule etc you’re using.