It is never be a representation of real world. So here are my own responses using his analysis of simulation models. It is true that we cannot logically prove that a model is true. But maybe their way of defining 'verify' is too strict. That makes all empirical knowledge impossible.
Extra factors can affect the result.
But still a simulation model is creating knowledge about the real world when the system is isolated or other factors are negligible. Don't take underdetermination too seriously. Often it is hard to find only one reasonable solution. Don't take assumption ladenness too seriously, either. Making reasonable assumptions Robustness 5.