This paper proposes novel advanced modeling techniques for capturing accurate RF impairments in a network digital twin workflow. A new DPD solution based on the recently invented Dynamic Gain model is introduced to evaluate how linearizable an amplifier is for both simulated and measured results. The modeling of active impedance and power amplifier load-pull is used to add realism to mmWave phased array designs for terrestrial and non-terrestrial applications. Incorporation of high-fidelity physical layer models in network-level simulation and validation with realistic complex scenarios for design-to-test workflows is demonstrated.