Well, one could be conservative and say that it is misleading; but if it is misleading, it is inherently false (my logic being that if it is only "half-true", it is essentially not true, i.e. false).  We cannot make such general statements about anarcho-capitalism in this case; we must clarify what Rothbard means when he says "he has the right to own the product that he has made."  

Socialists believe, unconditionally, in "the individual's right to possess what he or she produced."   Anarcho-capitalists, on the other hand, believe in the individual's right to possess what he or she produced (not merely obtained, such as through trade), if the product was made using previously unowned natural resources.  And to address your point, Vision Thing, trade does not necessarily imply a contractual division of labour, for trade is possible in economic systems such as mutualism, which do not recognize a division of labour.  Even if your statement were true, Vision Thing, we shouldn't be confusing or misleading readers with vague implications and paradoxes.