Which network or platform won Outstanding Documentary or Nonfiction Series at the 78th Emmy Awards? If a winning series was a co-production between multiple networks, identify the first-billed network on the official Emmys.com winner list. If the winner was Disney+ or National Geographic, count it as 'Disney+ / National Geographic'. If the winner was HBO or Max, count it as 'HBO / Max'. If a network not listed won, state 'Other'.