Test 4: Validating duplicate detection...
Found 3 duplicate groups:
  - John Doe: 2 duplicate(s)
  - Jane Smith: 1 duplicate(s)
  - Alice Brown: 1 duplicate(s)
ERROR: Expected duplicate group for 'John Smith' not found
ERROR: Expected duplicate group for 'Sarah Johnson' not found
ERROR: Expected duplicate group for 'Michael Brown' not found
ERROR: Expected duplicate group for 'Jennifer Davis' not found
ERROR: Expected duplicate group for 'Robert Wilson' not found
ERROR: Expected duplicate group for 'Lisa Anderson' not found

ERROR: Missing 6 expected duplicate groups