how can I verifiy if the ignition module is bad
Why do you think it is bad? Have you checked to see if you have any spark to the engine?
Your mechanic can use the repair manual, an electrical multimeter, and the wiring diagrams, to test the ignition system (a system has all of the components, including the ignition module, sensor, etc.). Changing parts, willy nilly, isn’t troubleshooting, and isn’t advised; but, hey!, if that’s the approach you want to use, it’s up to you).
You can take it to AutoZone, they have a test set for those things.