Murray is the one responsible for Jackson's death. He has served a measly 2-years on a 4-year sentence regarding the criminally negligent homicide and bears the brunt of the blame. AEG had nothing to gain from Jackson's passing. The tour would have made them money.
As LaToya Jackson pointed out a few years ago, echoing the Judiciary Report's previous claims, Sony is the one who had the most to gain from Jackson's death. They've made a fortune in posthumous sales off Jackson, as they did with Whitney Houston's passing and that of other singers. Jackson's death also makes it easier for Sony to gain full control over the Sony/ATV catalog, ram packed with copyright infringing songs the company keeps stealing from various songwriters, which Jackson co-owned.