In 1969 Kalmbach reprinted a book, originally published in 1916, titled "Passenger Terminals and Trains". The author was John A. Droege, General Superintendent, New York of the New York, New Haven and Hartford Railroad. There was an interesting topic in Chapter XIV, Car-cleaning Plants. In pre-WWI Germany, the railroads carried emigrant groups from interior Europe to northern German ports. One unintended consequence was passenger equipment, infested with vermin, including bed bugs. After experimentation with chemicals alone, which were not entirely satisfactory, they developed the following process:
1. The car to be treated was moved into a large (!) metal cylinder, which was then sealed at both ends
2. The cylinder was heated to 114 to 122 degrees F.
3. Air was evacuated from the cylinder
4. Formalin (whatever that is) was injected into the vacuum.
As a result, the car was de-pested and "disinfected" (the term the book used - probably, strictly speaking, not at an absolute bacterial or viral level). The process was effective because pests (including bed bugs), although they could survive heat or vacuum alone, could not tolerate both. Further, the process penetrated wall spaces and upholstery. The author indicated that the equipment setup cost $18,000 and that it processed one car per day, taking 10 hours and costing $8.33 per car. This was in 1909. They calculated that the alternate method required 10 times more labor with an uncertain outcome.
The term "crude but effective" comes to mind. The investment in equipment, time and labor would rule out such a process today and, maybe even back then, since I have no idea as to whether it was done for any length of time in Germany or elsewhere. One car per day is not very productive.
As for Amtrak and such a process:
1. It would take a really large cylinder for a Superliner car.
2. The sensitive electricals and electronics might not tolerate such a process
3. The process still could not be used to debug software issues in the car systems (heh-heh).