I deleted the text earlier today, and I installed iOS 16 within the past hour.
As we have stated, you have to install iOS 16 first.....then delete the message for it to appear in Recently Deleted.
Your wife must have deleted a few messages.....or.....iCloud updated some deleted messages.....after.....iOS 16 was installed.
As a test.......delete a message that you no longer need. Wait a few minutes, then see if Recently Deleted has activated. iOS 16 makes it a lot easier to retrieve a deleted message, but you can't delete a message then expect to retrieve it 40 days later.