Should I call the guy?

A friend of mine is interested in this guy and he seemed interested as well. They didn't date exclusively, but went out a couple of times with other people.

I met him when I was out with them two times.

Now the guy stopped answering my friend's calls and he asked for my number from a third person like two weeks ago.

He called me the other day, but I was busy and didn't pick up the phone and I wasn't sure the of the number (I don't have his number).

Now my friend wants me to call him to see what he wanted (since he just disappeared without calling her back). I don''t feel like calling him cause first of all I'm not interested and I don't want to get in the middle of the situation. Problem is my friend is disappointed in me cause she wants me to call him to know what he wants from me.

Should I call him for my friend's sake? Or should I do what makes me comfortable?