Autumn 1904 - MAO should have gone to Spain with support from Mars. The Channel should have gone to MAO. In Spring, when Liverpool goes to IRI, with IRI, MAO, Por, Spain, Gas and Mars, you would have Italy sealed out of the south.
Germany should have sent Den -> Kiel, Kiel -> Balt, Mun -> Burg, Sil -> Mun in Spring 1905. You would have had the line right there in 1905. That Germany NMRed is just rotten luck, it had nothing to do with the 4 CDs.
Even post the NMR you had a highly likely defense if you'd not disbanded StP - and got rid of Belgium instead, and Germany had retreated to Ruhr.
Look, the point of this post is not to criticize your play, it's just to show that some basic line awareness and tactical forethought can lead to stalemates in many situations, and it isn't any more than you'd expect to see even in a gunboat, if you have quality players. You'd said 'He won because France, Turkey, Russia and Austria all CD'd or missed a few turns' in your OP, this is not completely true. He certainly got strong because of it, but he didn't win because of it.