P1773 Honda -2001 accord 6cyl, automatic problem

Question

I had a single car accident where I swerved to avoid being rear ended and lost control. The car spun around several times with me pressing as hard as I could on the brakes. Afterward a three foot concrete road divider stopped the car as I was skidding backwards I coasted over to the shoulder. When I finally drove it to the exit it got up to about 40-50 mph. After sitting in the car to recuperate emotionally I drove it home. Then it wouldn't shift gears or go more than 30mph. I'm trying to sell it as is and want to be honest about the condition. A mechanic came to look at it today and used his electronic device to check it out. He showed me the readout which said, P1773 manufacturer control transmission. Also the "TCS" light is on and D4 is lite ( for the gears). I think the transmission needs replacing but am afraid to drive it anywhere to find out.