Harvey did a super job with the records he was able to find. Mostly from the gaming commission and as stated in the front- many burned.
Why discount any casino not in his book?
I have countless hours into research and have probably 500 clubs he does not list with proof of gaming! Many early clubs had poker way before the legalization of gaming. Right now I can not find it on this Bank Club but will show you when I do. Harvey was a wonderful man and gave greatly to our hobby but dont think he could of found every little casino.
Did you know there were many gaming houses along the train tracks all over Nevada? So small that probably nothing will be found, and many just had slots.