AWS validation fails - Azure validation works

[API_User]

I am able to successfully create a connection to "AWS Direct Connect" via the APIs. However, the docs recommends in step 5:

5. Validate your AWS Account ID

Use the Validate Connection Authorization Key API request to verify that your AWS Account ID can be used to create a connection to the selected service profile in the given metro.

Doing a POST to /fabric/v4/connections/validate

{
    "filter": {
        "and": [
            {
                "property": "/zSide/accessPoint/authenticationKey",
                "operator": "=",
                "values": [
                    "123456789"
                ]
            },
            {
                "property": "/zSide/accessPoint/profile/uuid",
                "operator": "=",
                "values": [
                    "69ee618d-be52-468d-bc99-00566f2dd2b9"
                ]
            }
        ]
    }
}

and it always returns a 400 Bad Request

[
    {
        "errorCode": "EQ-3142601",
        "errorMessage": "Error while validating Authorization Key",
        "details": "The connection type is not supported",
        "correlationId": "null-0000-104889776726-api"
    }
]

On the other hand, I can validate an Azure authentication key and get a successful response. Am I missing something for the AWS validation?