Well which one is it a "termination discrepency" or a wrong date? If your dates are not perfect that in itself is not a big deal. Although if you are omitting a termination from a former employer you may have shot yourself in the foot. If they find out before or during the polygraph exam you will be DQ'd. I could be wrong but isn't a termination from a job usually negative? Thought thats why they called it a termination not a resignation.
Again call you BI asap or you will be in for some sad times.

Anxiety