Problem with Form API getOwner

System

I am using Form API to basically capture an audit trail of user/date-time of modifications to each DCR. I am having a problem with the value for IWDCRInfo.getDCRName(). It only populates with my name. I am the branch owner and manager of the security group for the pages -- I'm not sure if that is relevant or not. The documentation says that getOwner:

"Determines the owner of the file. In the TeamSite file system, the owner of the file is the last user to have modified the file."

I am having a co-worker update the DCR and this field remains populated with my name, even though the TeamSite interface shows his name in the "modified By" column. My intent is to use to update the DCR field with the onSaveValid event. But even when I populate a JavaScript alert onLoad, it always returns my name. I have success with using IWDCRInfo.getModificationDate(), so I seem to be on the right track. Here's a snippet:

var myOwnerData = IWDCRInfo.getOwner();
var myOwnerField = IWDatacapture.getItem("/dcr/updated_by/mod_owner");
myOwnerField.setValue(myOwnerData);
return true;

Any advice will be greatly appreciated.

Thanks,

Tami