According to EN 50129, manufacturers of rail vehicles shall justify via a safety case that their vehicles are adequately safe for their intended applications. MBASafe is a recently proposed and potentially innovative design and verification process. In the presence of compelling arguments concerning its adequacy as process evidence, MBASafe could support the safety claims within the required safety cases. In this paper, we contribute to partially justify the adequacy of MBASafe to act as process evidence. To do that, we first manually check if MBASafe includes EN 50128-compliant process elements, then we model MBASafe in compliance with Software Process Engineering Meta-model 2.0, then, we derive process-based arguments from the MBASafe process model by using MDSafeCer, the recently introduced Model Driven Safety Certification method. By doing so, we provide a twofold contribution: we further validate MDSafeCer in the rail domain and we strengthen MBASafe.