The most important point is that any digital printer (particularly those using CMYK inks) always has a defined gamut that represents the achievable colors for the print condition that is being used. The print condition includes the media, media profile, ink restrictions, and other factors that are in play when printing into a specific media.
The color gamut is finite, and if the desired color is significantly outside of it, we will not be able to make that color happen, in spite of our best efforts. The good news is that these gamuts can be modeled, and color matches can be accurately predicted. In the image below, I am showing the Pantone color 165C's position in relation to a media profile for 3M IJ40 on a CMYK digital printer. It is immediately apparent that the Pantone color's position is a ways outside of the gamut hull for the media. This color, Pantone 165C cannot be achieved using this print condition, regardless of how badly we would like to make it happen.
Another print condition, where different ink restrictions are being used, or another printer with other inks (such as Orange ink) might well be able to render this Pantone color, or at least get a lot closer, but not this one.
You can use multiple strikes in an effort to get more ink down onto the media, but run the risk of over saturating the vinyl with ink, which will cause bleed, and makes for much longer drying times.
Paul