That's the way it is! Simple SMDR (station message detail reporting) generates only one record per call, and the entire call is credited to the last person who spoke. So if you're gonna call somebody you shouldn't, transfer the call to voice mail before hanging up and VM will get charged with the call.
The 5000 CAN do detailed reporting including showing ring, talk and hold time for each station the call touched, even those that didn't answer. But this function uses CTI (computer telephony integration). Given enough man-hours you could write software to use that info, but it's easier to buy Mitel Business Dashboard (now renamed MiContactCenter Office). List price is about $2150, plus you'll need to turn on licenses for OAI EVents and OAI Third Party Call Control on the 5000. There are upgraded versions of this that include real-time screens and agent reporting as well.