I have not seen this issue before but in the Pdf attached the first thing I noticed was on the left side at zero the Finished Ground seems to continue beyond EG line to the left.
On the Sections that do report an area does the FG surface tie into the EG surface within left & right limits of the section view?
I have had this happen before.
The solution was given to me via this forum in 2011. Possibly by Matt Kolberg.
It was to move one of the comparison surfaces a miniscule distance (0.0005m).
I was working with several different models and the problem was happening all over the place with no apparent pattern. This solution worked on every model that gave me problems.
It blew my mind at the time and still does.
Good luck.