Ahhh... I understand now.
I have never seen an option to disable sending the invite to the 'invitees' when you first create the meeting. I guess I'm a little puzzled why the client *wouldn't* want the invitees to know about the meeting....but it's not my place to question why
If you don't want to send the meeting to them, then I'd recommend not adding them as an invitee, but rather just putting their names in the body/subject/notes of the meeting.
As for the Oracle issue....that one I can't help with...sorry!