I don't get that sense.
Where were the other three bodies when the Ambassador was detected?
That has never been clear to me but my general assumption is that they were killed at a different location.
Sean Smith probably died of smoke inhalation (judging by the pictures of the burned out room and some testimony that I read)
There is so much misinformation and rumor, etc. surrounding this horrible event, a true and accurate narrative and timeline are pretty hard to make, isn't it.