I’ll try:
I have no idea if this is going to work, but you need to do something during the ‘h,’ part of your IVR context. I don’t have any code, and I’m not even sure it is going to do what you need, but that (to my simple way of thinking) is where your code needs to be.
There are a couple of “send e-mail in the event of so-and-so” in the system.
My thoughts - if you get to the “h,” parf of an IVR, it means that the connection is hung up. It works like the “s,” part (where ‘s’ is startup).
Look through your /var/log/asterisk/full file and see what happens when a call gets abandoned. That will tell you the context and phase you want to start looking in.
I’m almost certain this is going to be a “deep magic” change to the system. I don’t think anything anywhere in the current system is going to get you started on this.