Ok, sorry for the misplaced advice. Good luck with the school!
Who is your target market? For an adult to take nearly a year out of their life is a big ask. For whom do you expect it will be worth it? Staff/campaigners at existing non-profits? Existing bloggers/youtubers etc on related subjects? Anyone else? How large is the potential pool of students and how will you reach them and convince them that the course is worth the time and money?
I realise this is not a commercial project, but I think you would benefit from some start-up like thinking: who is this product for, what is the market, how do you reach customers, what is a minimum viable product from which to iterate? Apologies if you have already done that, but it wasn't communicated in your post.
One other factor, which I would class under demand factors: at each stage of the industrial revolution, you need to have enough demand for the primitive early version of your new technology, so that people will use it, iterate on it, and develop it.
You write "early Newcomen engines consumed ~45 pounds of coal per horsepower-hour; the most efficient engines of the late 1800s used less than one pound." But to get to those efficient engines, it had to be worth someone's while to use the very inefficient early Newcomen's engines, so that there was a version 1 which could be iterated into the 1lb/hp-hour version.
Bret Devereaux has an argument that this was specific to Britain, whose geology happens to contain lots of coal mines which were prone to flooding. (I recommend reading the whole thing.) So the very first use of a steam engine was to pump water out of coal mines. Because the use case was literally at the coal mine, there were zero transport costs for the coal (a major consideration in an era before railroads and steamships). The very inefficient Newcomen engines still raised more coal than they burned, which would otherwise have been inaccessible, so there was an economic use for them. The UK by this point had already cleared most of its forests, so there was demand for coal (not necessarily true in earlier periods). And the higher wages in England, which you discuss, meant it was cheaper to pump the water with steam engine than with muscle power even where muscle power was technically practical. His argument is effectively that without all of these factors, the very inefficient early steam engines would not have been economic, so no one would have iterated on them.
I don't think this is the only factor - you/Allen have gone through a lot of others, which also make sense. But I think it's worth considering that part of the answer to 'why did the Industrial Revolution start in England?' is geological accident.