Because i am stumbled about this campaign during the FSPort Single Player missions, i am remembering this seperated voice acted release back then.
Actually i wonder, if there is a complete version of this campaign available somewhere? All links in this thread that are working does only have a version of the campaign without Mandala Prime in the last mission. And that is the only version i have myself.
https://dl.dropboxusercontent.com/u/101702076/mandalaprime.vpI had the same problem (missing Mandala Prime) a long time ago. Admiral Nelson sent me that^ file and it fixed things. Could you put that in your DOP folder and see if it works?