If we say {juHvamvo' jIHaw'}, the "getting out" carries a sense of urgency.
But lets see it in reverse. Can I say {jIHaw'} without the "I flee", carrying with it a sense of "getting out" ?
How can you say {jIHaw'} without the "I flee"? That's what it means!
I think you're being confused by the idiomatic "get out" in the word's gloss. It doesn't necessarily refer to exiting a room or other enclosure. It just means going away with a quickness.
Perhaps it would help for you to see an actual example of a Klingon saying "Get out!"
From Star Trek III: The Search for Spock:
TORG: My Lord. The ship appears to be deserted.
KRUGE: How can that be? They're hiding!
TORG: Yes sir. But the bridge appears to be run by computer. It is the only thing speaking.
KRUGE: Speaking? Let me hear.
COMPUTER VOICE: Nine, ...eight, ...seven, ...six, ...five,...
KRUGE: Get out! Get out of there! Get out!
COMPUTER VOICE: ...one...
ENTERPRISE: *kaboom*
It was filmed in English, but you can see the intended usage.
-- ghunchu'wI'