There are two problems with this. First, your position is completely contrary to the facts, and second, the question is stupid.
I'll address the latter first: To know what it feels like to be a mouse, in the immediate sense, you have to be a mouse. And a mouse lacks the mental faculties to know that it knows what it feels like to be a mouse. The question has not been answered because the question is set up so that it cannot be answered.
However, more broadly, it is being answered. While it is impossible in principle to know in the sense of immediate apprehension what it is like to be a mouse and still retain the faculties to analyse or communicate this, it is perfectly possible to analyse to problem from many angles and come to an intellectual understanding of the question, and indeed we have made considerable progress both generall and specifically in this area.