Razer Viper Ultimate Help

So about 2 years back, I bought a Razer Viper Ultimate on eBay. It was discontinued like so long ago, but I've always wanted a pink mouse, and this mouse looks and feels PERFECT.

But it broke. One day it was able to charge, and the next day it wasn't. I bought a replacement battery on eBay and swapped it out. The battery worked, but it was never able to charge back up. It used up the energy stored in the battery, and it died again a few hours later. The charger works, the battery is brand new, and the charging dock works too. Do I need to replace the Motherboard?

Also, for anyone wondering why I can't just get a new mouse, it cost me like 150+ with the dock, and I personally love the absolute shit outta this mouse and don't want a new one.

I've tried to go to Razer support, but since I didn't buy it from them, they were unwilling to help, even if I paid for the replacement parts.

Also, if anyone knows what to do, can you let me know where I can find a replacement part? The only place I found giving replacement parts is AliExpress, and I'd prefer to order from somewhere else if possible.