Reviewing Sheriff Sills' comment on movement of Mr. Dermond's body, he only said to the effect, "...maybe a couple of feet..." He did make any statement indicating it was a fact that the killing(s) took place elsewhere.
It is only an assumption that a boat was used to approach the home. It is not necessarily fact that a boat was used to remove/place/transport Mrs. Dermond's body.
Interesting quote from the sheriff, " ...placed..., or in the vicinity...", when referring to Mrs. Dermond's corpse location.
We don't know for sure.
Maybe they moved the body just enough to make it easier to do what they did to RD.
I thought the place/transport implied that either could have been the case. Meaning she , SD, could have been dumped and floated where found or actually placed where found.
I wouldn't think her body would have ended up where it did had a boat not been used. IF they dumped her from shore somewhere could she have floated there all while searches were being conducted and never seen?
HMMMMM