Summary
The simulation on logistics module does not consider the price product matching the minimum and maximum value on Shipping Policy to provide the available shipping policies when the price product is ZERO. It means if the simulation does not have the product price the simulation provides Shipping Policies that can not be actually available due Minimum and Maximum value.
Simulation
You must have one Shipping Policy with Minimum and Maximum value configured. After that simulate it with product without price.
Example: Set the Minimum as $10 and Maximum value as $100 on Shipping Policy. After that, on simulation does not put the product price. You will see the Shipping Policy as availabe to deliver.
But the expected result for that is not shows that Shipping Policy because only products between $10 and $100 should be delivered.
Workaround
Execute the simulation with product price.