Good Day Jacqueline
I am not sure if there is a way to disable or remove the option for outbound agent greeting.
You can however only upload or recording an "inbound" recording under the agent greeting which will only play on inbound calls for the specific queue. I tested it on my side where I had the audio loaded for outbound but not for inbound. When making an outbound call I could hear the agent greeting, on inbound I did not hear the recording.
Hope this answers your question.

Regards
Stephan
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Stephan Taljaard
EMBEDIT s.r.o
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