It's not paradolia. The edges and shading of the mystery figure, are too precise and exact. It is a definite image of a figure. There is no denying it. The lighting on the figure is even similar to the guys in the foreground - sun above. With crisp sharp continuous lines like that, with no kinks or dents, that's not wishful thinking.
As for the two guys in the foreground, it was mentioned the shadow from the sun on their heads is different, suggesting they were individually photographed at different times of the day. I disagree. The fella on the left is stooped forward and his head tilted to the left, hence the shadow falls down over his torso and more on his left shoulder. It is a bigger shadow than the other fellow's who is sitting more upright with his head back, and shadow not falling below his scapula at the top of his chest.
As for the figure. It's very similar to the fella on the left. The fella on the left is sitting on his hands with his legs together, whereas the figure behind is stooped forward with his arms resting on his thighs, with legs apart. The hairstyle of the fella on the left with head forward, forms a slight peek at the back. There also seems to be a stick resting vertically next to the fella on the left's left arm and a similar stick in the left hand area of the mystery figure.
With old photos like this, the proof isnt in the photo, it's in THE NEGATIVE and whatever photos were taken immediately before and after this one. I can only assume the negative no longer exists.
While Mr Jones certainly comes across as a sincere senior citizen in the interviews (where butter wouldn't melt in his mouth), who knows what his character was like, sixty years earlier, or if the story from sixty years earlier matches his 1990's version?
I'm thinking, whether there was or wasn't double exposure involved, someone has very possibly had some fun tampering with the photo, adding shades and black and white to highlight the figure, using the fella on the left as a rough guide.
Otherwise, if that exact image exists on a film negative somewhere (which I'm confident it doesnt), that's a yowie, man!