Hey,
You can use StarWind VSAN free to create a small replicated device to run as a disk witness for your cluster. In this case, if one of sites fails it will still have a connection to witness drive. Check the following guide for more:
https://www.starwindsoftware.com/resource-library/starwind-virtual-san-for-hyper-v-2-node-hyperconverged-scenario-with-windows-server-2016/#975a9857211a3b66215d3a2bb624b10e77312268
Cheers,
Alex Bykovskyi
StarWind Software
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