The Con analysis fails with the error message, "Error 000732" where it is unable to utilize input raster from an environment workspace when running the analysis as a script tool in ArcGIS Pro.
Run the script through IDLE, the ArcGIS Pro Python environment (Python 3.6.5) instead of as a script tool.
Run the script as tool through ArcMap 10.6.1.
Run the Con analysis from a script tool in ArcGIS Pro where the input, true and false rasters are established as file paths and not from an environment workspace.