I'm posting this as a favor of a friend of mine who has a 96-98 Pass-
port. Here's what he told me happened. He was starting the Passport and thinks he inadverently was pressing on one of the keyless entry
buttons while trying to start it. It did not start and now everything is
DEAD! No electrical-lights, ignition, warning buzzers, NOTHING. I
suggested he check all the fuses. He says he disconnected the battery
incase it has something to do with the computer (although I'm not
sure how that will help-ingorant me). Vehicle was working fine until then without any symptoms that anything was wrong.

Any ideas as how to check this vehicle out?

Thanks

there should be a main relay under the hood in the fuse box. I think there is more then one, so you could swap one around with an existing one to see if it solves the problem.