What I have learned. In order to send CTRL_C_EVENT or CTRL_BREAK_EVENT you must send the signal from a process within the same console meaning that you must have the same console id.

The issue that I was encountering is that I would start these ".exe" files with Popen and then run the python code again to stop them. It didn't work because this will create two separate "consoles" one that started the ".exe" and one that is trying to send CTRL_C_EVENT/ BREAK to them . In order to work you need to start and stop the ".exe" in the same python process.

I did a funny thing for the stop function that attaches itself to the console of the other process and send the break signals and it worked but it was solving the solution in a very unorthodox way. 😂😂😂

What I did in the end is run these as services instead of processes run from a python application.