From reading back on the subject it appears that the forensics officers was too fat to get over the wall so the gathering of evidence was suspended until someone else could be brought to the scene. Not Lothian & Borders Police' finest moment in anyone's book.
I think it was pretty shocking to say the least and very disrespectful to the deceased person whatever the circumstances but especially so when even to the untrained eye it must have been obvious this was not an accidental death.
It was a difficult situation admittedly. It was after dark. Erecting a tent among trees and bushes in the dark might have damaged the crime scene by trying to preserve it being compromised more than waiting for daylight would have.
There must have been some police procedures which were put in place immediately. For example mounting a guard. I think the big holdup was the availability of the coroner.
I've not read anything about exactly what steps were taken to preserve the scene without damaging it more. Logic dictates there must have been protocols. In the absence of a detailed breakdown of what the police actually did (and given they were acutely aware this was a child's deposition site) the best bet for an informed opinion would be John, because given the timing and the location we could be making a harsh judgement.