Solution
This issue is caused by a bug in the LabWindows/CVI 2019 + LabWindows Real-Time installation process. Specifically, the NI-SWITCH Real-Time driver files are not correctly installed to the following directory:
C:\Program Files (x86)\National Instruments\RT Images\NI-SWITCH\19.0
As a result, NI MAX cannot detect or deploy the NI-SWITCH driver to the RT target. In contrast, when NI-SWITCH is installed in a LabVIEW 2019 + LabVIEW Real-Time environment, the RT Images folder is correctly populated, and NI-SWITCH appears as expected in NI MAX.
To resolve the issue, copy the NI-SWITCH RT Images folder from a system where LabVIEW 2019 + LabVIEW Real-Time + NI-SWITCH 19.0 are properly installed. Then manually place the folder on the affected system. After doing so, restart NI MAX and attempt to deploy the driver again to the RT target.