Desktop Duplication Api does not work in Mosaic mode

Windows10 pro 20H2, 2xGPU Nvidia Quadro P4000 in MosaicMode
To capture the screen in Mosaic mode, we use DesktopDuplicationApi.
IDXGIOutputDuplication is created without error, but when AcquireNextFrame (…) is called, it always returns DXGI_ERROR_ACCESS_LOST
this problem is reproduced on official sample app https://github.com/NVIDIA/video-sdk-samples/tree/master/nvEncDXGIOutputDuplicationSample
and https://github.com/microsoft/Windows-classic-samples/tree/master/Samples/DXGIDesktopDuplication

NvFBC screen capture works without problems, but it is deprecated
when Mosaic mode is disabled, each card individually works with IDXGIOutputDuplication without problems

Is this a bug or is DesktopDuplicationApi not supported in Mosaic mode ??

NVIDIA System Information 11-12-2020 15-29-38.txt (5.0 KB)