I would bet the window regulator assembly is shot. You will need to take the panel off to see what is going on, but broken or frayed cables on them are common. Hopefully there will be a part number on it so that you can get a new one if that is what the problem is. They are readily available at Napa, and they aren't difficult to change (I have done 2 of them on my GMC Yukon this year).
I believe Triple E is still operating at a reduced capacity so you may be able to contact them to enquire as to what regulator they used back then.
