The sample data tables are installed when JMP is installed on your computer. If they were deleted after that, you can always reload them by reinstalling JMP.
If your organization eliminates the sample data during it's install, the only option I can think of, is do download a trial version of JMP, which will download the sample data tables.
If this is not the issue, there is a Sample Data Files section of the JMP Community that has data tables available for download
JMP Community Sample Data
Jim