It's because she is a narcissist and she knows best.
At all points in this whole shitshow anyone else would have reached out to people who know more about these type of things.
She should have known, and was almost certainly told, about what the contract for the allotment would contain.
With a CIC, anyone else would have reached out to an already established CIC for advice. If you all for advice people are usually happy to help.
With the school thing, most people would have approached a school, told them about your idea to bring allotments into schools, tell them you would fund it, and ask them if they are interested, and if they are then what does the school feel would be the best way to implement it if it is possible.
Let the school lead, as they have all of the experience and knowledge of what would be possible in that particular school.
She's out there on social media talking a load of bollocks about what she thinks will make her look like the biggest hero.
Having an allotment in a school is not going to change a child's life, they will not become an entrepreneur or a gardener based on an hour or so a week digging dirt and pulling weeds. They would find it enjoyable and get to see things grow and it would be fun. But it's not going to change lives.
She makes everything about her, even feeding people is about her and not the people, hence all the screenshots to show the world she's a wonderful person.
In my experience, if you bring an idea or a problem to a school, they almost always have a way to do it better and a way to solve a problem that you didn't even know could be done. They are the school experts and you would be insane not to let them lead.