I would see cognitive science and philosophy of mind as two aspects of one indivisible discipline, even if carried out in different departments (maybe less so now again). Philosophy of mind deals with the basic questions without direct reference to specific new observational or data gathering exercises. Cognitive science deals with applying those exercises to questions and may be unable to address some of the questions the philosophers discuss.

In practical terms cognitive science needs philosophy because it needs to be clear what questions make sense. As I see it there is a major problem at present because most people in cognitive science assume that Descartes was wrong to posit internal 'experiencing units' yet it is hard to see how one can have an account consistent with physical science without these. Unfortunately philosophers also seem to think Descartes was wrong, so they are not much help. 

A simple example of how philosophy of mind needs cognitive science is in that cognitive science shows empirically that 'enactive' approaches to perception are wrong or at least without any truth evaluable content. The same probably goes for 'embodied' and 'extended' models although it is not very clear what these really involve much of the time.

Of course,  the suggested question "How Can Philosophy Be a True Cognitive Science?" is incoherent since all science exists,  necessarily,  in a philosophical framework.  For "knowledge of things" itself must subsist in an environment where there exists knowledge of "how to know".  That is,  science presupposes epistemology.  (Incidentally,  this becomes very clear when reading William of Ockam's "Summa Logicae".) 

Philosophy cannot be science since science requires a philosophical context.  (Unless of course you are using the old meaning of "science" as "knowledge",  but this is excluded by the adjective in "Cognitive Science".)

There is at present a large gap between the sorts of things (using the wide meaning of "thing" as "entity") that can be the object of Cognitive Science,  and those things that can be the objects of Philosophy of Mind.  The one set of things is tied down to physical incarnations (bits of the brain),  but the other set of things remain,  strictly speaking,  ineffable (consciousness,  purpose,  intention,  coherence etc) even if they are very obviously there.  We have so far made approximately zero progress in forging links between these two realms.  It seems to me that Jonathan Edwards' very interesting observation (for which I would like more details,  please) that "cognitive science shows empirically that 'enactive' approaches to perception are wrong" is a case in point.  He is saying that the science has ruled out one possible link.