I received this note from Keysight: "With IOLS 2024 and IOLS 2024 Update 1, the R&D team has developed and included the Keysight Instrument IO Service. This service has a "KIIS" server running in the background that provides a REST API to extract instrument information added into Keysight IO Libraries Suite's GUI -> Connection Expert. This means that if the customer has versions of IO Libraries Suite that are older than the 2024 version, the workaround below will not work. The customer can download these newer versions of IOLS from here: www.keysight.com/find/iosuite"

Basically, this is OK but not trivial. I am going to rename all our DVMs uniquely ModelNo-SerialNo, and require our test software to use those IDs.