Is there really a Wei Xiaobao in history?

I remember it seems that in the postscript of Duke Lushan (or I may have read Kong Dong Qing's book), Wei Xiaobao's prototype is a mixture of Nian Gengyao and Longco. At the end of the novel, it is mentioned that the Kangxi school knew that Wei Xiaobao's court guards were looking for Wei Xiaobao among the people, and then Cao Xueqin's ancestors went to Wei Xiaobao.