Cyn, has it been ststed how long a decomposed body will emit an odor? For this type of drag marks to still be evident(greasy) wouldn't that indicate the body had not been there for 27 days but a lesser time as Faulkner and Haskell said? Collins said the area was dry,leaves were dry.
Entrails (intestines) would leave the marks.
The body was dried so the odor not as strong as you would expect and the unusual insect activity.
The animals did not open up the body until later, so the drag marks would be made more recently than the body laying there.