Comments appeared to help so I'm including it as an answer:
One way to sort items with spaces in their object property names is to pass a predicate sort function into orderBy
instead of specifying the object property name. The relevant modifications in particular:
HTML:
<li ng-repeat="credit in credits | orderBy:predicate">
JS:
$scope.predicate = function(val) {
// $scope.corder corresponds to the object property name to sort by
return val[$scope.corder];
}
Demonstration Plunker.