The fire timing seems odd. They return home from vacation just after the fire breaks out? What are the odds of that? All I can think is they had something programmed to turn on just as they returned (a coffee pot or something) but even that seems odd because who can predict their return down to the minute and the fire must have started within minutes of their return or the house would have burned down before they got there. Maybe something was smoldering and the fire went up when they opened the door but that doesn't jive with the report that they found it on fire when they returned.
Doesn't this seem odd to the rest of you or have I just forgotten to take my medication today?
If at first you don't succeed set fire to something. It probably won't help but it will make your failure more festive. Almost a celebration. My Feedback