There seems to be a bit of confusion over where everything is happening so I have made a map.
https://imgur.com/a/dAbeb
The police tent and portaloo are by the entrance to the field next to the quarry. Gaia was not found there, it is just the most convenient place for the police to put their toilets.
Based on the photos and where they were flying their drone when they found the clothes they were scattered in the part of the field marked with the yellow circle. There is a stone wall around the field about 5ft high with a gate at either side on the east and west walls. The footpath runs parallel to the southern wall of the field but the path is well below the height of the wall so you wouldn't be able to see over it. This time of year the footpath is muddy so Gaia may have jumped the gates and crossed the fields to save getting muddy. She knows that area so she would know it as a shortcut.
Based on the police search area yesterday Gaia was somewhere in the blue area. An educated guess based on the location of the clothes and her direction of travel I would think she was somewhere in the top left of the blue area. There is a steep drop, about 30ft or more, down the side of the hill into the gorse and blackthorn bushes below so if she was stumbling around in the dark and disorientated she would only have to walk off of the footpath a few degrees and end up falling down the hill.