Which brand of novel proteins are you feeding? I see it raw, but was wondering if manufactured or you are making it. I'm just checking if you are feeding him low carb food and whether there's a way to get his dose increased any faster until you get to a better dose. I see you are missing a good number of the preshots tests. We strongly suggest getting preshot tests for each and every shot, to make sure it's safe to give insulin. With Levemir, it's not unusual for a kitty to nadir around preshot time. And when cabergoline does start to work, you'll have to be vigilant about testing to keep him safe.
I'd also either put that you started cabergoline and the date in your signature, or highlight it somehow the spreadsheet so it's easier to see. As Suzanne said, you can try every day and see how it goes. What dose of cabergoline are you giving, and how much does he weigh?