There would be tens of millions involved in finishing the engineering and building an autmated factory. People with kind of money are not stupid and do due diligence.
Some people with that kind of money are smart. Others are stupid. How else do you explain things like the 2008 real estate crash and the $120 million wasted on Juicero? The history of business is chock full of disastrous investments made by stupid wealthy people.
There are also drastic non-investments. In the 1980s, DEC was the second largest computer company. DEC and all minicomputer companies drove themselves out of business by refusing to invest in personal computers. If they had deliberately set out to destroy themselves they could not have done it more effectively. It was as if their business strategy was dictated by their competitors. This was clear to me and to everyone else in the computer business at the time. Hundreds of billions of dollars in capital went down the drain. And you say people will not waste $10 million?
That is not to suggest that business people are especially stupid. You will find disastrous mistakes in every other institution. See, for example, World War I, especially the Battle of the Somme and the Gallipoli campaign; the invasions of Russia by Napoleon and Hitler; and the U.S. Army and Navy dispositions and lack of preparation at Pearl Harbor in 1941. In aviation, read about the R101 airship disaster or the Challenger explosion. In programming, look at the roll-out of the Obamacare website. See the book "March of Folly" for other examples.
History is full of stupid mistakes. There were actually more of them than most history books show, because they are often covered up or de-emphasized. Stupid mistakes made by influential people are often written out of the history books. If -- as I fear -- cold fusion is forgotten in the future, that will be a gigantic mistake. The people who made that mistake at places like the DoE and Nature will never be held responsible. Researchers such as Fleischmann will be blamed (if the story ever surfaces). Perhaps they do share a minor fraction of the blame, but they are more sinned against than sinning.