The coefficient by itself doesn’t tell the whole story, as you also need a reference length to go with it. So, it will depend on what that length is. For example, for a yawing or pitching moment, does the sim use the wingspan, semi-span or mean aerodynamic chord as the reference length? That’s part of it.
My theory is that they are not calculating 3D lift slopes for tail surfaces. That is, corrected for aspect ratio and sweep. They are using 2D lift data for an airfoil ( I think ). Also, they are not factoring in downwash from the wing in the lift slope of the tail surfaces, which would cut the tail lift in 1/2, approximately. So, when you combine those things, you could easily see a factor of 5 or more.
Moments of inertia also play a huge role in the yaw or pitch response. More testing is required. A work around would be to reduce the htail and vtail areas by “the factor”. Here’s an example for a vertical tail
2d lift slope = 0.1 / deg
3d lift slope for aspect ratio 1.5 with 30 deg of sweep = 0.037 / deg