AS3 GSLB_Pool - How to add members?

I am using AS3 to deploy LTM and DNS configs to a pair of standalone BIG-IPs in a DNS Sync Group.

Everything works and I can add a virtual server to a GSLB_Pool if that virtual server is defined in this AS3 declaration.

However, I need to add a virtual server to the pool that is in the other BIG-IP, configured as a server in a second data center. Auto discovery is configured but AS3 won't accept the second pool member saying that the object doesn't exist.

See the snippet below. Obviously I haven't posted the whole thing but the red section is what fails. vs_prod_dc1 is defined in this declaration (redacted) but vs_prod_dc2 is defined in another declaration because it's for a different BIG-IP.

What am I missing here?

"DC1": {
    "class": "GSLB_Data_Center"
},
"DC2": {
    "class": "GSLB_Data_Center"
},
"F5-A": {
    "class": "GSLB_Server",
    "dataCenter": {
        "use": "DC1"
    },
    "devices": [
        {
            "address": "172.16.20.1"
        }
    ],
    "virtualServerDiscoveryMode": "enabled-no-delete"
},
"F5-B": {
    "class": "GSLB_Server",
    "dataCenter": {
        "use": "DC2"
    },
    "devices": [
        {
            "address": "172.16.20.2"
        }
    ],
    "virtualServerDiscoveryMode": "enabled-no-delete"
}



"dns_pool_prod": {
    "class": "GSLB_Pool",
    "resourceRecordType": "A",
    "members": [
        {
            "server": {
                "use": "/Common/Shared/F5-A"
            },
            "virtualServer": {
                "use": "vs_prod_dc1"
            }
        },
        {
            "server": {
                "use": "/Common/Shared/F5-B"
            },
            "virtualServer": {
                "use": "vs_prod_dc2"
            }
        }
    ]
}