God, so many twists and turns!
Makes ya wonder if perhaps the "timing" of WM's death could have something to do with WW. Perhaps since his posting in 2008 he did end up meeting and developing a relationship w/ WM..........and maybe if it's true that WM was engaged and planning to marry he was going to be going to his lawyer to have a prenup agreement drawn up and his will revised which would include WW, DM got wind of it and was INCENSED and outraged and either he did or was responsible for the death of his father, not only as revenge but because he didn't want to ever have to share WM's estate/fortune with some half-brother....so he killed him while he (DM) was still the only heir.
So many possibilities.
Money and greed. Two very big motivators.