And that looks even more like someone has been scratched out.
You're right ... The more / most 'original' digital photo far more clearly portrays a full human figure that's been obscured / removed from the final edition of the photo. Furthermore, it shows that the figure is / was in front of the propeller shaft - something that's not discernible in the high-contrast version to which you linked.
(And because of this I retract my plate roughness / simulacrum guess.)
However ... This figure isn't 'scratched out' - it's been blurred by daubing in the darkroom or afterward - probably by a liquid solvent on a swab or brush. If you look closely you can make out the sinuous patterns of strokes associated with the action. Scratching leaves much more ragged / jagged remnants.
If you look above and to the right of the rightmost man you'll see a set of smears or abrasions that extend across both hull plates behind and shaft bearing in the foreground. I strongly suspect these are abrasions caused by the arm of whoever was daubing the mystery figure out of the scene.
This 'most original' version also shows that the missing figure's left hand and lowermost pants legs and shoes don't seem to have been touched / daubed at all. On the other hand, they're much less clearly defined and less contrast-y than other visible elements - suggesting they could be remnants of a possibly inadvertent double exposure.
It would be an odd ghost whose fuzzy versus more 'solid' aspects were strictly delimited by, or correlated with the borders of, surrounding objects.
Another odd bit is that there seems to be a pretty clearly demarcated vertical line serving as the boundary of the daubed / still-visible area beneath the shaft. It's enough to make me wonder whether part of the modification to this photo involved overlaying or inserting a piece from another shot of the same posed scene (e.g., one in which an additional worker had been added or one of the visible ones had been posed in a difference place).
The mystery figure is taller than the one man standing in front of the shaft to the left, so I don't think it represents a second exposure of him in a similar pose at a different position. The figure's height is, however, a close match to the rightmost guy standing behind the shaft.
It seems to me there's plenty of reason to believe this photo was significantly manipulated in the darkroom.