The car is still in the shop. They replaced the battery cables. "The technician is still testing it," the "Service Coordinator" told me over the phone. "He wants to try it out again in the morning, to make sure."
One of two things is happening here:
The technician is being very thorough and careful, since this is an "intermittent" problem.
They don't really know if the $300 battery cables are the solution to the problem.