Q:

Is it okay to link to another answer in my answer, in order to link two questions? 

On the question How can I access the Ethernet port's I/O on a hardware level in Mac OS X?,  I initlally commented and then put a link in to another answer as my answer. 
The answer I linked to is Mac driver development, and superficially it looks like a duplicate, however the question where I posted my answer is a more precise question (or use case).  
I think the latter is the answer to this in a general sense, but not specifically to the question about the headers. 
I don't know if any of this is 'right'. 

A:

Yes of course it's OK to link to another answer, so long as it helps you answer the question.  What you want to avoid is making that link the entirety of your answer.  If this happens, either the question is a duplicate, or... you haven't properly answered the question. 
FWIW, when you see a question that looks at first glance to be a duplicate of another, but has subtle differences that make the answers to the first unsuitable, consider revising it to emphasize those differences.  I've done this on your example.  The questions look nothing the same now...

