In this case you must choose different fixup to do that, because that second spot color is something that giving an error. In this example I will show you how to convert spot color to specific destination CMYK.
You can modify your existing Spot color conversion fixup.

Find «Convert colors» fixup in the list.
Set settings in Destination as it is shown below.
Remember that I choose for you U.S. Web Coated (SWOP) v2 profile. If you are in Europe, you would prefer to use PSO or ISO profiles, if you want to print in the end.

Switch to Conversion settings and select to convert All Objects.
Then be sure to select that you want to convert Spot Colors. It would be better to use Absolute Colorimetric rendering intent.
Run the fixup and enjoy the results.
