This is what TN law has to say on the matter.
39-11-611 (c)
Any person using force intended or likely to cause death or serious bodily injury within a residence, business, dwelling or vehicle is presumed to have held a reasonable belief of imminent death or serious bodily injury to self, family, a member of the household or a person visiting as an invited guest, when that force is used against another person, who unlawfully and forcibly enters or has unlawfully and forcibly entered the residence, business, dwelling or vehicle, and the person using defensive force knew or had reason to believe that an unlawful and forcible entry occurred.
I'm reading that as a presumption of deadly force being justified in the described areas if the boldened is met. Assuming there is credible evidence in CW's scenario that the person had in fact forcibly broken through a window and was in the process of entering the home it certainly reads as though deadly force can be brought into play.