Possibly - although I think the FBI can tell whether the doors were opened simultaneously. Sure, if you think that BM would take the chance of strapping his dead wife into the passenger's seat of a vehicle and risk the body moving in very unlife-like ways during a road trip, that could have happened.
Which would mean she was killed at home in between her last convo with JL and about 5 minutes before that door opened on the passenger side.
At any rate, it's the next time that door opens that's interesting (because apparently, LE doesn't believe that next time can be certainly a living Suzanne.
So, as bizarre as it sounds, you could be right. I have to say that if that happened, I'm shocked - but if Barry really did stop at the sandwich shop next, in Poncha, with Suzanne propped up in the truck, oh my!
(But at this point...I can't really be shocked).