The chances that this is an accident are pretty low. Putin wanted to get as little blowback as possible from knocking him off, since he's widely popular. I'm sure he didn't think twice about murdering 9 other innocent people at the same time.
Everybody in that list were high ranks in the Wagner group. All supporting if not directly commiting many atrocities and war crimes in Sudan, Syria or Ukranie. We talk of a group executing people with hammers or cutting their hands and beheading them while recording all, and sending the video to all the contacts in the phone of the victim.
Calling them "innocent people" is extremely generous.
The most interesting part is how carefully the killer assured to behead the top of the group at the same time in one single hit.