The connector is really one of the most problematic parts of the whole flexible printed circuit board. It isn't designed to be mended or serviced save through outright replacement. Furthermore, the connection style is particular to the Vanagon. Even if you could resurface or reattach the exposed leads in some way, the fix would be temporary at best, breaking whenever you need to disconnect the cluster. Hence my use of the DB25 connector (an idea borrowed from fellow list member Ed M.)

Fast Forward has these, which might be connected to a damaged flexible circuit and then connected to the existing vanagon plug for the instrument cluster. (Look for Cockpit Converter on the page).
http://www.fastforward.ca/harness_retrofit_accessories.html 

I agree with Neil and Alistair's assessment that the best solution is rewiring the entire cluster.

-Jarrrett