@Chuckz
The Microsoft Enterprise Connected Cache node is intended to be installed on a Windows Server where the Windows clients use that cache server.
Since XCP-ng cannot do nested virtualization, you are correct: the use Microsoft Enterprise Connected Cache is not available unless a separate server running Windows bare-metal or Hyper-V (or ESXi, ...) with nested virtualization enabled.
Most places use a hypervisor on all bare-metal servers and virtualize the compute. That was my situation. Which means I was unable to improve InTune Win32 app deployment, because we had switched to XCP-ng.