Got you. Your solution is already fairly sophisticated.
Instead of dipping into the controller for this how about connecting some sort of addressable smart power meter. Maybe even part of the same solution as the dead switch microcontroller solution. A power meter would be a fairly consistent measure of usage.
Or is getting the specific named project files significant? Which by the way may be a reused temporary file name. Trying to think of a natural “odometer” on the controller side… check this link from Rick. He talks about some of what’s in the controller. Don’t know if these can be queried.
You should review this thread for more general information. I don’t think it would be particularly difficult to query the controller for some basic information although there’s some obfuscation going on in the communication layer from what I recall.