A Cessna 208B, when adapted, can hold up to 21 people, IIRC. It wouldn’t work for 9 people to be in the cargo area because the plane would be imbalanced. The cargo area could hold a few though.
There is a reason, though, that Lang’s photos are photoshopped. We have no idea what all was in the sky or the water when this crash happened.
Mark Miller claims that there was a navy plane in the area at the time which reported the crash. The USCG says they got the first report, from the Honolulu Control Facility after they received a report by somebody flying closeby, at 3:27, which is exactly when the FAA report says that the crash happened. There was no ELT signal, according to the FAA. So unless there was monkey business with the HCF, there was an aircraft that was right there when the crash happened - before Lang ever appeared, according to his story.
Whatever aircraft that was could easily have provided whatever “extras” didn’t fit in the Cessna, as well as the equipment seen in the Puentes video.
Seriously, ask yourself a simple question - why have such a massive plot to carry this out, thereby significantly increasing the chance of detection? Why not just break into her home and make it look like a robbery gone bad?