Based on your questions, retaining a lawyer will definitely help! You seem to be describing the E-2 treaty investor visa, but only Taiwan is a treaty country, not China proper. Your investor would be better served going right into the EB-5 program. His investment would need to be “at-risk” which would probably prohibit the investor from making a loan to the company. By sticking with the EB-5 program, he can live anywhere in the U.S., but needs to have active management rights (voting on matters of the company, primarily).
You ask several interesting questions which definitely require the advise and direction of an experienced EB-5 Attorney. Please note the filing of an investors petition which either shows how the investors funds has already been committed or in the process of being invested, the investor does not have to be in the U.S. In addition, the investor can be a minority owner of the U.S.business and the investor can play a minor managerial role.