Sorry to here that.
Must agree with mcramsay, but if no one is able to fathom the wiring, you may be left with those options.
We are all good at diagnosing from afar, and we have not actually seen what you have, but anything is usually fixable given time and a little knowledge. The time is the big factor, and if you need to use a professional, the most costly part. And not always the best option, remember you have a one off,a Bespoke setup, no info, no diagrams, and to be fair, no professional will have training for that scenario.
It I a case of costing your options, but I would also include, the DIY option, using help from this and other forums, you will just need to be prepared to have a go, research, and ask questions, but you are free, it'd just a case of your time, and how much you cost that.
Sorry if not much help.