
Electrical problems, such as crazy computer problems, are likely loose or dirty electrical connections, whether it be where the computer connects to the battery terminals (if it does directly), or any connector may need cleaning and adjustment, which can be tedious and requires patience and skill. In very old cars, wire insulation can fail either by cracking and falling apart, especially in places exposed to much heat, or long term vibration wears a hole into the insulation causing a short.
Most anything can be fixed, it's just a matter of time, cost, and the knowledge and skill of the particular repair man. If they say it can't be fixed, they just don't know how, or think (and could be right) that the cost to fix is higher than another car. That being said, computers can be repaired, rebuilt, or replaced. I don't know the cost, but replacing with an identical used one from a junkyard would be the only option likely less than $1-2k (just a guess).
Your husband should try searching for similar problems with that model of car to see what others have found it out to be, just in case the Honda dealer has troubles figuring it out. Dealers like quick fixes, so if that means just swapping out parts rather than identifying the exact problem and cause, it could cost a lot.