Which ones? Which company actually has put out a consistent, significant, structurally sound high speed rail network including stations and the trains themselves that is based in the US?
And headhunting foreign talent tells me that you have not worked in the rail planning sector. These companies are extraordinarily protective of their high value who are the executive "talent" behind their stuff. And the biggest rail tech companies are multinational conglomerates (Alstombardier, Siemens, CRRC, Hitachi) who have no desire or need to outsource to America.
There is noone currently who has both intimate knowledge of American geodetic planning and high stress track planning. And building that knowledge takes a lot of trial and error.