I don't know what the default DCB would be, maybe recfm=u? You're going to have to show us the message.
Thinking about it, I'm not certain you can define a PDS with a reference to a member at the same time. To put it another way, I don't think you can. Look up the message. If you think it might help, pre-allocate the PDS, and remove everything except DSN and DISP, which you change to OLD.