There you are via API:
$ curl -s -k -X GET --header "Content-Type:application/json" --header 'Accept: application/json' --header "Authorization: Bearer $token" 'https://vra.corp.local/catalog-service/api/consumer/requests/c638f786-1a61-4a94-ac07-65facf17d715/forms/details' | jq '.values.entries[] | select (.key == "provider-arg_out_0") | .value.value'
"my workflow output"