The last person to approach the couple was a short, elderly woman who smiled as she congratulated them — not by name but as "wife" and "husband". (Para. 5)
Meaning: The last person to get close to greet the couple was a short, old woman.
When she greeted them, she smiled and simply called them "wife" and "husband".
congratulate: vt. express good luck or pleasure at (someone's) success
She congratulated him on winning a prize. 她祝贺他得了奖。