After Sarah and Sheridan have their conversation in the corridor, the jammer is left in place against the wall. Sarah had forgotten to retrieve it.
Throughout the story, the fugitive is called "Dr. Jacobs". When they use the station's scanners to search for him, the computer screen refers to him as "Jacoby".
Since neither Sarah nor Sheridan turn off the jamming device immediately after their clandestine conversation, it would be impossible for Sheridan to call Garibaldi on the link.