Noted. Thanks.
The damage to the main ICs seems like a plausible location for a problem. HuC6280's pin 16's trace to ground is damaged for example. All the silicon makes it rather difficult to get a good look at whats going on with the pins. However, without knowing when it stopped working it's difficult to know where to start.
I've already invested more time into this than it's probably worth. May end up being a parts board.