Inform the uploader that the file is broken

You might want to try extracting with WinRAR first though, as a rule is 7-zip doesn't work for any reason then try WinRAR (free version is enough for that)

Normally though you would be able to just mount that via the MDS like you attempted to do, so long as the Devil May Cry 3 SE.I0x are in the same folder as the *.mds file