I would be willing to bet money that these people were dead BEFORE the fire, which would explain why the fire was set.  To try to hide evidence the culprits knew the police were probably paid NOT to LOOK FOR.  What is going on in America with all the mysterious fires?  Living in the midst of a highly wooded area, where for years the US Forest Service was not allowed to do the job of cleaning up slash piles *thank you dumbass obozo* is a little bit scary.  If these hills ever started on fire, there would be no end to the destruction of about 16 towns and cities.  ALL PRODUCTIVE PLACES LIKE DEADWOOD, STURGIS, LEAD, RAPID CITY, WALL - - all the way from thick forests to the badlands would burn.  The only way it would stop is to reach the badlands where there IS NOTHING TO BURN.  ROCKS DON'T BURN!!  But it's far too difficult to build anything over there in the badlands, and also far too hot this time of year.  Those rock formations are still sometimes holding summer heat in the middle of December.  SERIOUSLY.

A fire in this area would cost billions upon billions of dollars, not to mention many historic places would be destroyed.

https://www.westernjournal.com/mysterious-explosion-rocks-town-leaves-multiple-dead-multiple-places-hazmat-team-spotted/?ats_es=b1798f26764e0d5fc6b5dbba3b874b7e