It is quite possible for the battery to light to 4 dots, but be no good. I have one like that. It is still recognized, but drains to 0 about one minute after boot. Later, they get to the point where the Pismo knows it is borked and puts a red X on it.

Is there a friend with another Lombard/Pismo who could try the battery in their machine? I think the battery is far more likely to be the culprit than the charging circuit, but it does happen. The fact that you've updated the DC board makes me suspect the battery.

There's a guy in Florida on eBay who has sold 2-packs of new Pismo Apple brand batteries for about $50-55. I ordered from him with my fingers crossed. They really were new batteries and after a one day chargeup, work perfectly. I was so pleased. There are still some decent Pismo battery deals out there...