Brad,

If I were in your position, I would withdraw my application for employment with U.S. Customs and Border Protection. This agency has the highest reported pre-employment polygraph failure rate of any federal agency (roughly 70%). Failing the polygraph with any federal agency results in a lifetime bar from employment with that agency and will harm your prospects of employment with other federal agencies (even for positions without a polygraph requirement).

Note also that the fact that you rescheduled your polygraph the same day you were scheduled to take it may be interpreted by your polygraph operator as an indication that you are a liar.

For more on the shortcomings of polygraphy, and why it is prudent to avoid any federal agency with a pre-employment polygraph requirement, see The Lie Behind the Lie Detector:

https://antipolygraph.org/pubs.shtml