My first inclination is to say no.  He was complaining and not very patient I believe with what brought on him leaving (something about not being able to get help for SC strat).  We've all been frustrated on not getting a group right away before but have worked on other things while we wait for people to have time and energy to help us in a group.  

I don't like the idea of letting people ping-pong in and out of the guild much but on the other hand real life can bleed over into interactions in our little game here.  He seemed to be a solid guy before all this happens so I'll say I'm for letting him in once again to see if this doesn't happen again.l