If there ever was an argument with some weight as to some hidden meaning in the Morse Code, it would be the “RQ”.

By itself?  It is nothing.

So why go to the bother?

That kind of question has led me many times to assume it is meaningful.  That’s one outlook.  The other is that it is just random letters meant to throw us off.  That’s possible but since no one has assigned them any value and the first three parts were solved without them then the point is moot.  The other option is that someone crazy enough to put RQ on a lark might be too crazy for us to figure out for K4.

Time is your position as the shadow forces the virtually invisible … of a lucid memory.  -R.Q.