Triangle of death stumps the dealer!!

Hey techies, I just wanted to let you all know about a situation that I had with my 2004 Prius. First of all, let me tell you about my wife's car. 2004, 260,000 miles and looks like it was ridden hard and hung up wet! Anyways,... since we owned the car from new the maintenance has been kept up and the only things that has been major was replacing the AC compressor & I put in a new used (2009) set of batteries over a year ago. Anyways,... the triangle light of death came on and the ready light would not turn on so I couldn't put in in any gear. I put my scanner on it to check the codes and their were none but when I selected to clear the codes, the light turned off. After that I could put in in gear. After about 2 minutes, the light came back on again. To save a diagnostic fee from the dealer, I replaced the 12V battery and still had the same problem. I decided to take it to the dealer and they told me that I had a short in the transmission. I didn't even ask for an estimate! I did ask what years were compatible with my Gen II and they said up till 2009. I got a tranny from the same place I got my batteries from and it was from a 2008 with 36,000 miles. The Toyota Tech did say that a lot of the times when there is a short in the tranny, the Inverter might have had to work over time and it might be bad too. They didn't have any way to figure out exactly which one it was. Anyways,... 6 Hours of labor and $450 for the tranny, I finished the job. I started it up and the light came on again. I cleared everything and then drove it and as long as the engine was running, the light would stay off but as soon as I sat still for about 2 minutes, there it is again. I took it back to the dealer and this time there was no charge for the diagnostic but the same code came up again. (I'm sorry but I don't know the code #. I can ask) As I was warned before, I went back and picked up a 2008 inverter from the same car as the Tranny and that only took about 30 min to R&R and after another $400, I was finished. Yahoo!!! so I thought. After about 2 min, the light came back on. At this point, I now have some gas cans in the car and a road flair just in case I need to torch the poor thing. I went back to the dealer and by now the Tech feels like crap because on his recommendation, I have now put about $1000 into this POS and it still isn't working. I told him, (polity) please trouble shoot the car and be sure of what you find. He had it for over a week and he would call me every day with an update that he is still looking at it with other techs from another dealership. (by now even I told him of the gas and flair in the back) Anyways,... He called me and told me to come over. it didn't sound good. I went there and he told me with the service writer in front of us... he can't figure it out, Sorry dude. After the service writer left he called me back and showed me my problem. One side of my high voltage cables on the HV Batteries were chard from either a bad connection or something. I checked the cable and it was tight so I installed it ok when I replaced the batteries so we decided that it was from the tranny being shorted out. I asked him why did he tell me in front of the Service writer that he didn't figure it out? The reason why he told me that was so then the dealer couldn't charge me for the many hours of his diagnostic time. I later replaced the cables and that was a pain in the nice person just for that but now she is running good. I even poured the extra gas in the tank!
So after all this, if someone has a similar problem, check the battery connections on the HV batteries. JUST BE CAREFUL.