Yours isn't the only Tosa with a broken power connector plug. If yours has the same problem due to the stupid design flaw sticking the connector where it can easily loosen, I fixed mine's AC adapter plug for charging that way, by taking a heavy duty rubber band (like the ones that hold bunch carrots together), sliding the keyboard cover out and holding the plug in place by slipping the rubber band down over the bottom end of the cover, just below the joystick. Sorry no camera to post an image.
May be a different issue for yours, but if it's just loose, that makes it possible to run on AC or charge while using the unit (which I am doing right now).
Oh, yeah, I did wrap some tape around the connector cord as well, to make it fatter and less bendable for the first two inches.
sdjf