Prueba esto
Contacts.aggregate({$group: { "_id": { code: "$Code", name: "$Name" } } }, function(err, contacts) {
...
});
O, con $match
si necesita esta AgencyTranslation: /^BROADCASTING/
condición
Contacts.aggregate([
{ $match : { AgencyTranslation: /^BROADCASTING/ } },
{ $group: { "_id": { code: "$Code", name: "$Name" } } }
], function(err, contacts) {
// ...
});