Failure to return security deposit within 30 days

[Tom Rychlewski]

when my last renter moved out,  I tried to schedule a final walk through with her but she was too busy to do meet with me.  I performed by final inspection 6 days after the official end of the lease.  during my inspection I uncovered several damages including significant hard wood flooring damage caused by her pets.  I informed the renter that the damage to the floors alone would likely be over $500.  She pushed back and requested a 2nd opinion.  The process of getting a flooring company to come out and provide a quote to repair the floors in the most economical way possible ended up pushing my return of deposit letter and check to 32 days from the lease termination date.  My tenant is now threatening to take me to court for not providing her the entire security deposit within 30 days as required by Missouri Statute Section 535.300.  

I reduced the total amount she owed by 40% because she has been a good tenant up until this point.  What is my risk?  when is the official "termination of the tenancy?" Is it after inspection?  After she transfers utilities? Am i late if i am providing her with an estimate at her request?

If anyone has any experience here i would appreciate it!