Thre is more going on than you think there is. It's a paradigm that is true with every situation.

The child whose parents divorce feels that they are entirely responsible for the split. They're not.

The employee losing his job thinks it's all his fault. In almost every instance, it's not.

Likewise, you think your delay in responding to ATE's request was the direct cause of his departure. In reality, I doubt it played a signficant role.

ATE is an... intense... personality. There seems to be at least some history of that personality clashing with this site's management. I enjoyed reading Adam's posts and found the majority of his advice to be very helpful. But the writing was on the wall on this one long before the situation you describe occurred...