The first text at 4:34 was initiated by Jodi so you can be almost certain Luke was in the house at that point, no point being anywhere else if there were no plans made. There were a total of 4 text 2 from each of them not a lot to instigate much of what your saying. Let surmise that Luke was in the house at the last text at 4:38 pm he would have had to have left straight away to walk the 11 min road to be seen by Bryson at the entrance to that path. What time did he have to get everything needed to carry out a murder and forensically clean the scene and not be seen by anyone.