curl --request GET \
  --url https://statsigapi.net/console/v1/holdouts/{id}/overrides \
  --header 'STATSIG-API-KEY: <api-key>'

{
  "message": "Holdout Overrides read successfully.",
  "data": {
    "passingUserIDs": [
      "string"
    ],
    "failingUserIDs": [
      "string"
    ]
  }
}