It sounds like you have to be an EE in either event
Might as well put your efforts into something that isn't proprietary, assuming you are not on the toyota payroll.
What are the inputs, what about battery selection for regen, how about the motor(s)? when it decides not to run for lack of an engine then what? What if the voltage cutoffs are not appropriate an ev?
I've considered repurposing controllers before, I couldn't make it make sense, was easier to start over with a thorough understanding of what you wanted it to do.