While @colbyjd3 explained the benefits of high platforms, has the benefit of cars accessible from low platforms, both locomotive pulled (Bombardier Bi-Levels, the fresh sheet cars Alstom is making for Metra) and EMU (Stadler’s FLIRT line, the EMU’s they’re making for Caltrain) been compared in contrast? They may be a bit more feasible in terms of cost and are largely proven.
Also, do you have a plan if Duke decides to sabotage this try. I know the suggestion for a planned West Durham station has shuttle buses, probably operated by Duke as they have the fleet and they rotate through buses as it is, but given their petty past can they be overriden?