Changing the rail from an elevated guideway (hereinafter EG) to a ground level design is not a viable option because it has many issues Mr. Wilson ignores.
To date, there are 10.8 mi of completed EG, from E. Kapolei to Aloha Stadium.  There is a 43-acre maintenance and storage facility completed & intended to support driverless trains running on the EG.
The EG rail system is designed with a third rail which provides power to the train.  This design cannot be used at ground level because of the danger to the public.  To construct the remaining rail at ground level, the entire train system would require a redesign (add cost & delays).  The 10.8 mi of third rail on the EG would be wasted.
The MSF facility has a control center to operate the automated trains intended to travel on the EG.  However, driverless trains cannot be used to traveling at ground level & deal with cross traffic.
The train contract would require a change order (add cost & delays) to redesign the trains & oper. system.