00' 320CLK Transmission Harness

[foamy]

Hello out there!
I have a 2000 320CLK, the transmission harness seal leaked and the fluid found its way up to the computer and was causing slipping and all kinds of error messages on the dash display. The mechanic I got replaced the harness and seal and removed the module and blew air in it to dry it out. It runs great now no more slipping or strange error messages.
The issue is, he said that I should get rid of it because the computer will go pretty soon because of the fluid that got in there, that this was only a "band-aid" fix...this doesn't sound right to me. Its no longer acting up nor is it intermittent. Aren't shorted out parts either fried or not?
Thanks