Automatic Transmission Park/neutral Start Switch problems of the 2005 Toyota Avalon

2005 Toyota Avalon touring model taken in 5000 mile service with complaints about a noise coming from rear end or transmission. Toyota could not hear it until I insisted mechanic take ride me. Mechanic acknowledged noise and said maybe coming from computerized abs brake initiating at 5 mph. Wife parked at work just couple weeks after maintenance. Pulled into parking at work, stopped, put in park and in seconds the car lunged forward with engine revving at high speed; wife stomped on parking brake but by that time car jumped over 10 or 12 foot curb , a four foot sidewalk and into a wall just stopping as it hit the wall. Tire marks. Call to elmore Toyota garden grove (alan/service) who said they had no body shop and did not want to see car or need to check and work on it before body work. Said if no lights were on the dash there was nothing wrong. Just like their attitude about the ratcheting noise supposed from the abs brake system. Wife insists she did not the gas pedal accidentally . When engine revelation after hitting wall went back to normal, car put in reverse to back off side walk. State farm told us not to drive the car to body shop. How do we force Toyota to find the problem with this car.