curl --request POST \
  --url https://api.hubapi.com/marketing/v3/marketing-events/attendance/{externalEventId}/{subscriberState}/email-create \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "inputs": [
    {
      "contactProperties": {},
      "properties": {},
      "email": "<string>",
      "interactionDateTime": 123
    }
  ]
}'

{
  "completedAt": "2023-11-07T05:31:56Z",
  "numErrors": 123,
  "requestedAt": "2023-11-07T05:31:56Z",
  "startedAt": "2023-11-07T05:31:56Z",
  "links": {},
  "results": [
    {
      "vid": 123,
      "email": "<string>"
    }
  ],
  "errors": [
    {
      "subCategory": "",
      "context": "",
      "links": "",
      "id": "",
      "category": "",
      "message": "",
      "errors": "",
      "status": ""
    }
  ],
  "status": "PENDING"
}