How to put it the polite way.
The file I mailed you back had an attached svg with the exact gradient you wanted to reproduce.
Did it not work?
You can definitely make gradients with more than two steps.
{[(On a side note, for a logo, they are better be avoided for numerous reasons.)]}
Inkscape is based on the svg specification as much as possible.
Fills are described as attributes for objects, and, as far as svg goes you cannot add more than one fill attribute to the exact same object.
It's nothing to do with inkscape, it is somewhere the very basic of the idea behind svg.
(You can add a fill to an object, group it, and add another fill attribute to the group, but the two at a time won't get rendered.)
In case of adding a fill made with several object (grouped together), a better way would be to use
clipping instead.