PLEASE How to startup a database when you don't have some readwrite datafiles

Hi, please does any one knows how in Oracle 9.2 How can I startup a database when the read write datafiles were dropped and can't be recovered.
Some one forgot to leave them read only. In that datafiles there were not information, only empty tables. Finally this is not important.

There is only a full cold backup without that datafiles.

I can't simply connect and put them offline. CONN SYS/SAFI70613474_at_SAFI.WORLD AS SYSDBA SHUTDOWN;
STARTUP PFILE=E:\oraSAFI\init\initSAFI.ora MOUNT; ALTER DATABASE
 DATAFILE 'E:\OraSAFIReadOnly\DFL_a_SAFI' OFFLINE; ALTER DATABASE
 DATAFILE 'D:\ORASAFIREADONLY\DFL_b_IDX_SAFI' OFFLINE; ALTER DATABASE OPEN;
And set
READ_ONLY_OPEN_DELAYED = TRUE What I'm missing, please.

Thank you

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