Correction to my last post, after some more experimentation: "acpi.passthru.slicvendor" seems to require "acpi.passthru.slic". Combining "acpi.passthru.slicvendor" with a custom SLIC table doesn't seem possible. So the only way to have a SLIC table and matching OEM IDs in the VM is to pass through the host's SLIC table.
Was wondering if it is possible to change the MSDM key in the bios file from 2012 R2 STD (4GB43) to R2 Datacenter key. i tried opening the bios file in Winhex but didn't find the STD key in there. any help? thanks!