Sal,
I have probably mentioned before but the connection of postures does not and will never be the sole assessment of the relationship amongst a martial art.
Having practiced Luohanquan and Chuojiao/BaFanmen for most of my life I can tell you that the connection from an intention, power generation and derivation of posture are different between Luohan and Bafanmen. Lastly, you probably have not seen real Bafanmen, possibly only the Dongbei methods which are only a small segment from which we practice in Hebei.
Additionally, Wang Zhiguo was a well known Bafan master as were many others such as Li Gong prior to Zhao Canyi. There is a lot more history than you can find in texts available to you and I would suggest given your keen research interest that the only way is to practise the martial arts and search for roots in China not just in text.
When I complete the Bafanquan section of my site it may assist.
Kindest Regards
Wu Chanlong
http://www.satirio.com/ma/home.html