Because it is an SVG, it isn't a "font" in the traditional since, but rather a rendering of a font. So, you have to provide a fill paint in the element.
Here is a silly, never to be used in a real setting example that illustrates what is needed.
Basically, add an object to the #17 element, and name it fill, add a paint key to that object and set the paint's value to the color that you want. A binding will work as well, or other advanced things that don't really fit into the SCADA world.
Your element would have a structure like this:
17:
type: text
transform: matrix(1 0 0 1 412.8225 65.94)
fill:
paint: #FF8C00