Looking at the picture of that replacement charger you kindly posted, it appears that the only connectpr between this charger and all the various connectors, is ONLY 2 POLE!! Check the picture out carefully!
Therefore, it is apparently totally misleading to assume that because there are 3 or 4 pins on the original charger, that they all "DO SOMETHING!" other than to mechanically stabilise he connection more! Nothing electrically!!!
That is a very "telling" picture!!
What say you all?
Andy
PS. Possibly examining the DC charge cable from the original charger to the battery connector, may reveal that its only a 2 wire cable. Telling!!
Also, looking inside the battery, at the other side of that connector, will probably reveal that only 2 wires are connected, positive and negative!