I believe inmate lied about which daughter wet the bed because the bed wetting was the spark that ignited the rage. Of course, it is unlikely that he knew at the time that the blood testing would find the anomaly that each of the family members was of a different type ABO and thus the crime scene could be fairly easily read.

There was evidence that Kristen had wet her own bed I believe and there was evidence that Kimmie had wet her own bed as well as the master bed.

Here is how I think it started:
1.Colette went to MB to prepare for bed and found Kimmie asleep in the bed. Colette decided to finish her own toilette before putting Kimmie back in her own room.

2. inmate entered MB and found Colette sitting on the side of her bed taking down her hair. (one hair ribbon untied and on bedside table matching ribbon on floor; still tied/knotted w/ Collette hairs entangled in the knot)

3. inmate found Kimmie in bed and big wet spot and yanked top sheet and spread off the bed and started yelling at Colette to change the bed "right this minute"

4. Colette said something to the effect "if you are in such a hurry do it yourself" and kaboom!