Core Data, using NSExpressions, how can we get these results to also include Department names?

gistfile1.m

- (void)fetchDepartmentExpenditureTotals
{
    NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Department"];
    // get all departments
    request.predicate = nil;

    // perhaps a second fetch could get the names and sort the same way, but this feels kludgy
    NSSortDescriptor *sortDescriptor = [NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES];
    request.sortDescriptors = [NSArray arrayWithObject:sortDescriptor];
        
    // Expenditure is another Entity with total as an attribute, linked on Department as expenditure
    NSExpression *keyPathExpression = [NSExpression expressionForKeyPath:@"expenditure.total"];

    // select sum(expenditure.total)
    NSExpression *sumExpression = [NSExpression expressionForFunction:@"sum:" arguments:[NSArray arrayWithObject:keyPathExpression]];
    
    NSExpressionDescription *expressionDescription = [[NSExpressionDescription alloc] init];
    [expressionDescription setName:@"DepartmentTotal"];
    [expressionDescription setExpression:sumExpression];
    [expressionDescription setExpressionResultType:NSDecimalAttributeType];
    
    // select Department.name
    NSExpression *nameExpression = [NSExpression expressionForKeyPath:@"name"];
    NSExpressionDescription *nameExpressionDescription = [[NSExpressionDescription alloc] init];
    [nameExpressionDescription setName:@"DepartmentName"];
    [nameExpressionDescription setExpression:nameExpression];
    [nameExpressionDescription setExpressionResultType:NSStringAttributeType];

    [request setResultType:NSDictionaryResultType];

     [request setPropertiesToFetch:[NSArray arrayWithObjects:sumExpressionDescription,
                                   nameExpressionDescription,
                                   @"assignedChartingColor", // this is a relationship
                                   nil]];   
    NSError *error = nil;
    NSArray *results = (NSDictionary *)[self.managedObjectContext executeFetchRequest:request error:&error];
    
    if (error) {
        // handle error
        return;
    }
    // ...

}


- (UIColor *)chartingColorForDepartmentWithIndex:(NSUInteger)index
{
    NSArray *resultsArray = self.data; // the results array of the fetch above
    NSDictionary *resultsRowDictionary = [resultsArray objectAtIndex:index];

      // Color is the managed object of the entity that assignedChartingColor links to
    Color *colorManagedObject = [resultsRowDictionary objectForKey:@"assignedChartingColor"];
   
    NSLog(@"%@", resultsRowDictionary);
/* returns: 
*    DepartmentName = Orange;
*    DepartmentTotal = 12;
*    assignedChartingColor = "0x74d6540 <x-coredata://F0E24183-4D4F-46E1-8224-FC4D1496457B/Color/p5>";
* :( :( :(
*/ 

    // this would be what I'd want to do, but for now the objectForKey:@"assignedChartingColor" isn't returning a Color*
    UIColor *thisColor = colorManagedObject.color; // .color is a transient UIColor*
 
    return (thisColor ? thisColor : [UIColor clearColor]);
}