Sam, Great job mating these two, I went through my bayonet trends, to try and find "probabilities" on matching the bayonet also. Here are some close matches, Carter might have more (will check) but it looks like Erfurt/01 is your best bet to complete the set.
1898 Erfurt 3.G.G.R.1.35. JN
1899 Erfurt 3.G.R.3.162
190x Erfurt 3.G.G.R.1.142
1901 Erfurt 3.G.G.R.3.212