A few names here I recognise from another forum and they all live in hot humid places and are heavier than average camera users. Hong Kong is also hot and humid.
I've never had such a problem with my Bessas but I know that heat, humidity, sweat from the hands and high usage can cause this sort of a problem with camera covering - especially synthetic leather. There's probably little point in trying to repair the damaged covering - it will all be damaged to some extent by now. Recovering would seem to be the best option and I think the suggestion to use a half case in future is a good one.