Solution
There are some NI modules (like PXIe-43xx SC Express DAQ modules) with pins that are reserved specifically for communication with NI official accessories. These reserved pins are designated by "RSVD" in the pinout. When creating a custom PCB we recommend leaving these pins unconnected because they are reserved for very specific communications and will not have any functionality to the end user.
Note: NI technical support does not officially support custom terminal blocks. NI strongly recommends using official accessories, but also won't block customers from using custom accessories if there is a need behind it.