I have been reading here, but the threads move so fast I may have missed this. My sneaky brain had a thought.
I checked Mapquest and from Raleigh to Danville, VA is about 2 hours (85 miles approx). Drive to a motel, check in, leave your credit card to be charged. Drive back home, kill Michelle, drive back to motel in VA. You don't need to actually check out if you left your credit card. You may not have been remembered by anyone staying at the motel, just the clerk saw you check in. If you want a time to call, then maybe you called from the motel at 11:00 pm. After all, you were in your room then. Even if you used a cell phone, they could triangulate your position at the motel. If you didn't use your cell phone after that, and no one remembered seeing you there or not, then there would be no phone records after that call. For all anyone knows you were sleeping. Going back home and returning to the motel would fall into the estimated time of death.
I don't know if anyone put this forward, but sometimes I miss posts due to work and the sheer volume of the three threads. Great job everyone.