The window can only be unlocked from the inside.
All entrances are locked. All of them.
Astrid checked Adolin and then Arya. Shallan checked Arya and then Adolin.
Now for repetitions…
Burning a body would still result in the ashes being counted as a body
The five bodies allowed in this case belong to Arya, Adolin, Astrid, Shallin and Dalinar
No person was killed inbetween leaving the garage and the group entering the guest house
By killing a person, the murderer is then called a culprit
I refuse to repeat the last one.
The only time that the door was unlocked was when Astrid unlocked it from the first floor.
Astrid never left the first floor using a window.
Dalinar only entered the Guesthouse once