There's an American expression from the Old West--"He shot himself in the foot." It comes from a gunslinger who's not as fast as he thinks he is, and pulls the trigger before the gun's out of the holster--with painful results.

I think this writer shot himself in the foot big-time, and that's going to be obvious even to him before too long... and you were simply gracious and accommodating. I hope he gets over himself and sends you an apology.