Walden was ready the moment the ward came through the journals. He'd been waiting patiently for the situation to explode and it only took a split second run to his study and floo to the Foundation. He ignored the fact that he hated floo travel and that he was now covered in soot. His main priority was protecting his family while keeping himself and his cohorts out of harms way.
With wand in hand he exited the office with a grumble and hit the stairs. There was already mass chaos all around the centre but Walden quickly spotted Aloysius and interrupted the man's frantic searching with a well trained blast.