You can get latest EPMdocument from EPMDocumentMaster and then get the necessary information.
Sample code to get the last version of EPMDocument is as follows-
QuerySpec qs = new QuerySpec(EPMDocumentMaster.class);
EPMDocumentMaster master = null;
QueryResult qr = PersistenceHelper.manager.find((StatementSpec) qs);
System.out.println("Number of EPM Document Masters: " + qr.size() + "\n\n");
while (qr.hasMoreElements()) {
master = (EPMDocumentMaster) qr.nextElement();
System.out.println("***** Name ->"+ master.getName());
EPMDocument latest = (EPMDocument)wt.vc.VersionControlHelper.service.allVersionsOf(master).nextElement();
String versionLatest = wt.vc.VersionControlHelper.getVersionIdentifier(latest).getValue();
System.out.println("******** Identity -> "+ latest.getIdentity());
}