WOW. If this is the case EVERYONE in the flight crew screwed up. Either the Co-Pilot or Pilot is always in control. When one has to answer nature’s call a flight attendant will ride shotgun. This just doesn’t muster credibility.
My guess (as a recovering aircraft engineer) is a tear in the canopy over the flight deck. But that’s just a guess.
So you are saying as a “recovering aircraft engineer” that the flight deck bulkhead is a pressure bulkhead?
Apparently not in Europe. Just American policy.