Help! Wiring problems

I own three Prius taxi's all 2008's and have been very happy with them.
One of the cars was in a serious accident 15 months ago when a car running a red light hit the drivers side front quarter panel and part of the drivers side door. I was surprised when the car was not written off when they told me it would cost $13,500 to fix.

Two months after the accident I had to replace a spiral wire that after labor cost me around $1000. Three months ago the red triangle light came on and I took it to the dealer. They said I was lucky the car didn't catch on fire with all the wires that were burnt and blackened.
Because they could only work on the car an hour here and an hour there (something about not wanting to cause more trouble by having the power on for too long, something to do with the ECU) it was almost 6 weeks to get my car back after they checked and replaced any bad wires. The mechanic told me a lot of wires were 'barbed' and figured the open copper getting wet etc. must have caused the problems. He blamed the mechanics that installed the computer dispatch system and the security camera in the taxi for the barbed wires which they denied and were probably right when they said they most likely were damaged in the accident.

When I got the car back it cost me $1700 which was a deal considering all the hours put into checking and replacing wires.

Two weeks after getting the car back the red light was on again and the 12 volt battery was once again drained. This time he replace fuse for the cooling fan inverter and the inverter was leaking coolant and removed to repair leaky cooling lines . This bill was $430.

10 days ago the car once again had a drained battery which I took out to Toyota and they trickle charged it for me and said I should be ok which had me scratching my head because they hadn't figured out the cause of the battery draining itself. Last Friday night once again the battery was drained and car was broke down again.
Saturday morning I took the battery to Toyota for them to trickle charge again and I bought a brand new battery to get my Taxi going for the rest of the weekend. That new battery was drained within 24 hours and I put the recently trickle charged battery back in to make sure I could get the car to toyota.
I took the car to Toyota Monday and picked it up today with another bill for $370. They said they found another bad wire running from left front fuse panel to the ECU, apparently this wire was burnt.

Five hours after the car was supposedly fixed my driver calls me and tells me the red triangle light is on again and the battery is drained again. ( Excuse me while I bang my head on the computer desk)

Obviously the mechanic is not capable of figuring out what is causing the wires to cook and I have over $3000 spent since the accident on wiring problems. Plus all my down time and loss of income (thankfully I have a Honda Accord I kept as a back up car but don't put it on if the repairs are only a couple days)

Any ideas what could be causing the troubles and would you ask for a different mechanic. There is only one other hybrid mechanic at this Toyota dealership.

 

Thanks Patrick------ I will ask the mechanic tomorrow if he has tried that approach. As far as I can see is all he does is spots the bad wires and changes them. They gave me pictures of burnt wires at the multiplex Connectors and the connectors were pretty burnt and lucky we didn't have a fire.