I don't think you are responding to my question.
I'm responding, but don't seem to be hitting a "sweet" spot. Those are probablilities for finding matches of that length with those characteristics. In other words, pristine DNA chunks in man and mouse of length 300 with no mutations would be expected to "happen" in one out of 100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 "times".(if I got the number of zeroes right)