I believe the position of the CP is wrong:

When calculating the CP in Line 43 in simpleWingLoadParams.m
sin(Phi) is used. This causes a great error when the sweep angle is large.

Compare calculation process:

phi = deg2rad(30);
error = tan(phi) - sin(phi)
error =

    0.0774

Compare error 2-Point-Model vs. Tornado:

This was tested using the wing from the new/eVTOL "TiltrotorAircraft":
The C_m0 is closer to the values calculated with tornado:

2-Point-Model:

(without applying moment correction)

using sin(phi) C_m0 = -0,259

using tan(Phi) C_m0 = -0.2516

Tornado

C_m0 = -0.1477