appreciate knowing about this 的意思是“对被告知这件事有谢意”
While I do appreciate knowing about this,my understanding is that Jack is leader for "A" and "B".
句子是说
尽管我很感谢（你们/你）告诉我这个事情,但据我所知,杰克是"A" 或者是 "B" 的领导.
也希望点击“选为满意答案”及时采纳,