Passthrough for OculusVR on the 4.27-plus branch not working?

Hi all,
Currently using Unreal Engine version 4.27-plus, I added the updated OculusVR plugin (1.94) to enable Passthrough for a Mixed Reality GameMode. The problem is that it doesn’t work at all, Passthrough is configured as “Underlay” but remains black. The same engine/gameplay configuration works perfectly on the official OculusVR fork for version 4.27. I’d like to know if there’s a way to enable Passthrough on Unreal Engine version 4.27-plus.
Thanks in advance!