Using @aws_auth directive on query with multiple datasources

Summary of problem: @aws_auth directive does not provide full access to my query, which has multiple datasources.

I have a type, foobar that contains fields from two datasources:

type foobar{     foo: String! //from the foobar dynamodb table     bar: String  //also from foobar dybnamodb table     baz: String  //from the baz dynamodb table } 

And a query, listFoobars that is annotated with permission for Admin users (default permission is DENY):

listFoobars(filter: TableFoobarsFilterInput, limit: Int, nextToken:  String): FoobarsConnection @aws_auth(cognito_groups: ["Admin"]) 

When I run this query with a user from the “Admin” group, I am able to obtain the data for the foo and bar fields, but not baz, which gives the error:

"Not Authorized to access baz on type foobar" 

How can I enable full permission on this query?