The ISS doesn't accelerate. It is subject to an angular velocity. Not an angular acceleration.
Rowbotham ignored Coriolis effects of a cannon ball because there is none. The earth does not spin. This is why toilets don't flush in the opposite direction in the southern hemisphere, smoke doesn't spiral in the opposite direction, shot putters don't demand to throw east to west to break world records and ocean currents go anywhere they damned well please.

Aweome! Thanks for the fodder.
1) ISS does it accelerate? The argument that since it has angular acceleration that it must not have (linear) acceleration is simply an excluded middle fallacy. Please try again. You might do well to go back to the definition of acceleration and then determine it the direction (or magnitude) of the ISS changes. (Hint: It's obvious that the ISS has a varying linear velocity throughout its orbit.)
2) Does Rowbotham ignore the effect? Rowbotham is hardly ignoring it. He argues, in error, that the experiment demonstrates that Earth does not rotate. His argument that since the cannonball before landing did not travel over a mile from the launch point, the Earth doesn't rotate. Since he relies inherently on his conclusion regarding this experiment to conclude the Earth is flat, EnaG fails to show that the Earth is flat.
Oh, and your graph is irrelevant. Concentrate on the critique. Rowbotham is a failure.
Oh, and please provide the peer review you mentioned. I'd love to read it. By the way, that an article (or a book) has been peer-reviewed does not improve the validity of an article. The review could have dismissed as wrong the article, for example.