Almost as soon as DeSantis said it, posts appeared showing Democrats saying “monkey around” which is, incidentally, a whole other thing.
To say that “monkey it up” (which I’ve never actually heard before) is like “monkey around” (a very common phrase) is kinda like this:
Good: you crack me up.
Bad: you smoke crack.
Both phrases have the word crack, sure, but they have completely differently meanings.
Well, everyone was writing about it so I figured I had to take a crack at it.
faxxus 
http://www.hacker-dictionary.com/terms/monkey-up
This definition will benefit you.
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So that defines it in a computer-specific context. I’ve worked in the computing industry for decades and have never heard it. I probably learned “monkey around” when I was 8 or so. “Monkey around” is in far more common usage.
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