According to spec (http://spec.graphql.org/October2021/#sec-Errors.Error-result-format), GraphQL response can contain both errors and data at the same time. With current implementation this package throws the QueryError exception which only contains the first error details. So, right now there is no way to access the data that came with the error response.
The constructor of QueryError exception requires the full response. So may be we can have a property in this exception that will contain data?