The fact that Mackenzie wasn't "sexually assaulted" has perplexed me, because most murders like Mackenzie's have a sexual component to them. Why would she not have been sexually assaulted? Would love to hear other posters' ideas on this. Here's one scenario off the top of my head... based on nothing by conjecture:
Mackenzie may not have been raped because she was murdered by a young man at the behest of a young woman who was jealous that the young man had briefly been romantically interested in Mackenzie. To prove his loyalty to his girlfriend, he took care of Mackenzie, while the girlfriend watched, or possibly participated. Because both were involved in the murder, neither will turn on the other.
The brodie marks, if recent, would be something that a young guy with a system full of adrenaline would do. This may sound disgusting... but... a four-wheeler with a deer rack could carry a body to the dumping site and easily manipulate up and down the incline, along the shore, etc.
Anyway... all conjecture.
Anyone remember the name
Diane Zamora? Could be a similar situation. Not saying that it's probable, just saying that it's possible.