because when you do online backup, the page that already written to backup image may be changed during backup, therefore it request rollforward
if you cannot provide the logs to rollforward to bring the database to consistent point, you cannot use the database
if you don't have the log files
the only way is calling IBM，and let them patch the control file，
then you can connect to database, and you need to export data for ALL tables, and drop the database, create new db, import data
