Ke V/100rpm should be 18.95 kV/kRPM.
For the KL34-180-90, at 90V this should produce a max speed of 4,750 rpm with no load. At rated torque output, this drops to 3200 rpm.
We can calculate Kt from Ke (here). In Nm this is Kt = Ke * 0.0095. Kt is right at 0.18Nm/A.
I can't say whether Kelings info is accurate, but you can compare your calculations on a very similarly specced motor: ID33000 series (or noreg here).