Hello all, I have a problem I need guidance on from some people in the know.

All of this took place in a foreign country:

In 2009 I left company A to work for Company B.  About 3 months later company B, through no fault of my own could not afford to keep me on the payroll.  But they said I could keep them on my resume as long as I needed to avoid unemployment gaps.

    To make ends meet I started working at vastly inferior company C under a horrible boss.  I left there on bad terms after 4 months and returned to the U.S.

When I applied to the CIA, unthinkingly I didnt mention company C at all and just listed company B for the full tenure until my return to the U.S.  Company B is willing to say I was working for them at least part time during that period, so it's not an outright lie, but it's not the truth either.

my questions:
1) how much of my financial records/how deeply can the CIA dig to get at this information?  (keeping in mind this is in a foreign country)
2)  If I come clean and say I was not in fact working for company B for that whole period but in fact company C (neither of which are sensitive or related at all to the any work the cia does) would I be automatically kicked out for being a resume fluffer?

3)  Company C's boss will have nothing nice to say about me at all, Should I be more worried about the small lie being found out or this awful person ruining my life's goal?

am I screwed on this postion and should just give up?  my past is squeaky clean except for this (a little pot in college, none in more than 5 years.  No debts, no convictions).

I would just come clean and tell everything as it happened. At least this way, it will not be so burdensome on you. Let the cards fall where they may. If you are passed over by the CIA, it might be the best thing that ever happened to you. Chill and stop stressing.