Delayed reply, but what the heck...
If you have no idea HOW they should have done things better (not just WHAT they should have done better), then how are you able to determine that they were incompetent?
Maybe that is a solution going forward, but HOW were they or anyone else supposed to know it wasn't enough before the race?
How do you know they had enough water for 25,000? Would they have had enough water for 25,000 if conditions had been Death Valley-like? Would they have had twice as much water as needed for 25,000 if conditions had been 50 degrees and overcast?
For that matter HOW do they (or you for that matter) determine how much water 25,000 need? If YOU can't figure out how much 35,000 need, who's to say you'll do any better when confronted with 25,000?
You still have not properly read and understood what has been posted and asked. HOW do you know how much water 35,000 needed in those conditions? Based on experience and knowledge, they made an educated guess. They guessed too low.
You haven't said HOW they should have guessed better, but simply sat on your high horse and said "more water".