You send a courier with the ring to King Tinwulf II, with a letter explaining that it was found in your castle.
The courier returns after two weeks but without any reply from your senior, beyond words of gratitude.
957 AD, Winter
An envoy arrives from the Kiwi. Your wife rather quickly disappears from the throne room.
"Greetings, Grand Duke of Tven!" The envoy bows his head in respect. "I am here to ask, on behalf of my lord and master, King Amabarn II, that you return Lady Tasarina to the Kiwi Kingdom."
"Lady Tasarina is now the Duke's wife." The advisor explains briefly, and the envoy continues.
"We know that, but there is justice to be done! Lady Tasarina is suspected of having something to do with the tragic accident that claimed the life of her eldest brother and the designated heir, Beren, last summer."
"And what kind of accident that was?" The advisor pries, and the envoy answers:
"Lord Beren died from a bundle of poisonous flowers that were brought to his bedchamber by mistake, and Lady Tasarina, with her hobbies of gardening and flowercraft, governed over the Palace's garden just prior to her journey here."
A) "That is a bunch of horse dung! My wife is innocent, begone with you!"
B) "If it is such an important matter, then truly, legal documents and reports of investigations must be shown to me first."
C) "I can have Lady Tasarina returned to Kiwi, but only briefly, and with a detachment of Tvenian guards at her side."