Hi,
After checking the CBS log, you saw the error: HRESULT = 0x80073701 - ERROR_SXS_ASSEMBLY_MISSING.
Check the contents below this error message for any references to updated or related package information. This is probably why the role install failed.
Also you could check for update. If any security updates need to be installed. Installing them firstly to check.
If DISM and SCF command could not find errors (include in CBS.log), I suggest that you could perform a repair install by running setup.exe from the root of the Windows Server 2012 install media.
Hope this helps and please help to accept as Answer if the response is useful.
Best Regards,
Carl