It seems only linear elastic material properties were used. That would explain the huge forces computed in the simulation that are far above the experimental data.
The Tensile Strength properties in your material do not affect the simulation, they only support plotting Safety Factors results.
In Engineering Data, access the material models under the Plasticity category. The simplest one is Bilinear Isotropic Hardening. Put in the Yield Strength that you know, and use 0 for the Tangent Modulus. See how that changes the force in your simulation.