Several issues at play here:

1. I'm pretty sure the incident was reported to the airline captain. Whenever something like this happens, the airlines are notified immediately, and I'm assuming that the captain of the affected flight is notified by the airlines. That captain decides whether or not to pull from the gate or have additional searches made. I'm certain that under extraordinary circumstances, the airlines or LEOs can direct the captain to empty the plane in order to have it searched even if the captain doesn't deem it necessary.

2. I disagree that the plane had to be searched. The passenger had not boarded the plane yet. However, I do think that the passenger's checked luggage had to be removed immediately once the unusual discovery was made. Again, this is an airline issue. Perhaps TSA management should have insisted that the checked luggage be removed and searched; however, ultimately, it's an airline decision. Just to clarify, the only items airlines CANNOT allow on board aircraft are those that have NOT BEEN SCREENED by TSA or have NOT BEEN CLEARED by TSA. These items were screened and cleared by TSA.

3. I think that once word of the incident had reached upper management, the Nervous Nellies went into Over-Reaction Overload and what-iffed themselves into a frenzy, resulting in the unscheduled stop for additional searches. I've seen this sort of thing happen in many other organizations; wouldn't surprise me if that's what happened in this case. However, the fundamental facts are that the luggage was screened; the individual was screened and caught at the checkpoint BEFORE he could enter the sterile area; all the appropriate notifications were made on the ground. The process worked. The unscheduled stop and additional searches were unnecessary.