The documentation for jclSourceURIs (part of JobConfigurationLoad) says that it is REQUIRED (https://hackage.haskell.org/package/gogol-bigquery-0.4.0/docs/Network-Google-BigQuery-Types.html#v:jclSourceURIs).
When doing a load JobsInsert request with uploaded data (from a local file or a live stream) the request works with jclSourceURIs left unset. I would suggest noting this exception.