Radically different color between screen and print

The people who wrote colour guides generally do not understand anything about colour. They take a colour from screen, convert it to CMYK by the first random way they find, and set it as a standard. You're going to need to learn how to ignore the CMYK values completely. With luck there are RGB values that you can treat as sRGB , and convert to the CMYK given to you by your printer. 

Why all this? Because CMYK isn't any kind of standard colour. It's a recipe. This much cyan ink, that much magenta, so much yellow, and that much black. Now, there are different brands of ink, which are different colours. The way the printing press runs affects the colour. And especially the type of paper used. Newsprint colours are a very long way from glossy paper colours, even with the same brand of ink. In fact if you use the wrong recipe, you will get the newsprint paper too wet and it can literally fall apart. So using the right newsprint colours is not optional. Using your so called company standard could get you in very big trouble. 

Hello, did you do all those steps? https://www.youtube.com/watch?v=oZTCEwaA8xQ&ab_channel=ErinGipford

Are you using color books? Like Pantone or Trumatch? For any solid areas of color in your work, it's important to choose color from a physical sample, rather than relying on what you see on screen.

I use Pantone books (primarily the Color Bridge guide) and choose colors from the right-hand column, which are CMYK, rather than solid/spot colors (unless the job requires that). I have loaded into Illustrator the library of swatches from Pantone that corresponds to the color book I'm using. I then choose the numbered swatches directly from that library to apply to the art. Even then, I have to allow for some shifting of colors, but it's pretty accurate when I see the final printed piece. You'll notice when you use Pantone colors, they don't always look the same on screen as they do in the book, and that's why we use them. Screens can vary a lot. Also, talk to your printer, they may have some suggestions on using RGB and converting to CMYK.