Is anything required of my wife to absolve her of sin after our young daughter urinated on the Mus'haf I had left on the closet?

The most deserving of glorification is the Word of Allah, and the Mushaf must be protected from places of mischief and placed in a secure location out of the reach of children. If what was mentioned occurred without negligence, then there is nothing on the wife, and the child is not held accountable. However, if there was negligence and carelessness, then the wife must repent to Allah and give a good amount in charity.