Are you for real?! Most if not all cryptocurrenices out there are open source where majority forked their code out of original bitcoin. Zcash is not the only open source cryptocurrency and it was meant to be private coin, but they are not best in terms of privacy in my opinion as there are much better alternatives out there. Dash is also not private by default so it's not the best secretive version of bitcoin for sure, although they have funding to fund all sorts of activities to spread the word about dash which is why it could be good to invest to, but who knows.