If that’s the case, what purpose does tying up the victims serve? Especially if you are going to kill them anyways.
He’d want to get in and out as fast as possible, and restraints wouldn’t be necessary.
The intent might not have been to kill them, but then he lost control of the situation. I think this would be plausible in the "older boyfriend/stalker Jayme is forbidden to see comes to kidnap her" scenario. To be clear i'm not suggesting that the target wasn't Jayme (i agree with what seems to be the consensus here that a robbery gone bad or something is not likely).
not saying you're wrong just throwing out possibilities.