Same thing will happen to Bitcoin Gold, but much faster because nobody really cares about it and much more people moved into Bitcoin this time to get some.
It seems you are mistaken, I remember the price of Bitcoin Cash just dumped at first time after listed on Bittrex change.
Then, after few hours, the price of Bitcoin has pumped from bottom price ~0.01 BTC or 0.003 BTC (depends on the rates of exchange) to 0.1 BTC.
Did not stop there, it cotinue to increased to 0.4 BTC and this is the highest price of Bitcoin Cash (after 3 days listed on Bittrex exchange).
Bitcoin cash at the cost of bitcoin is even a greater mistake than not investing in bitcoin. It will become a pain after few months when bitcoin will cross 10k dollars. IF ever bitcoin cash had any capabilities or even a slight chance of surpassing or becoming equal to bitcoin, I would have definitely supported BCH but the reality is it does not worth anything. It is not even among the top altcoins and people don trust it very much.