Polygraphs
Would the secret service REALLY go so hard after a respected senior agent based solely on failing a polygraph? And he failed on the "did you violate secret service protocol" section which could mean something innocuous like "I took a leak on the lawn while I was walking patrol" or "I was staring at some crowd members cleavage instead of watching the rooftops." I mean these things are notoriously prone to false positives. Any number of ordinary conditions, even anxiety about taking the test, can cause someone to register a false answer when they're really telling the truth.
"Unless Alpert's covered in bacon grease, I don't think Hugo can track anything."