No interest in a role player big man who cannot play defense.
Not what this team at this moment in time.
Chris Wilcox already taking up that slot for us?
Pretty much, yeah.
To expand on my first comment ... It's more Murphy's position (PF) and the position of the other big men in the team that hurts Murphy's value here.
There is an abundance of power forwards and a lack of interior defenders (centers, defensive anchor, rim deterrent). There are a couple of really good options there at the four with Garnett, Bass, Wilcox and JaJuan Johnson. However, there is a lack of alternatives behind J.O'Neal. Garnett is the only other player on the roster capable of anchoring a defense. Short on numbers.
If they wanted a player like Murphy, then they'd need to move Bass or Wilcox in exchange for a defensive five.