The operator of pornhubcasino.com is Usoftgaming N.V. incorporated in Curacao.
The operator of pornhub.com is unknown.
As far as I know they're run by a company located in Luxembourg :
https://en.wikipedia.org/wiki/MindGeek Their operations are pretty transparent and their headquarters are located in Montreal, Quebec, Canada.
If you still wish to dig into the details,you can google for this dude who started the parent company : Fabian Thylmann
However,I still couldn't find any relation between the gambling site and them.
Neither could I. Trawled through the official Pornhub blog and the casino doesn't come up, so am pretty sure they're not affiliated. Discussions since 2016 also don't appear to link them, though it seems strange no one asked.
As pointed out above, combining two of the biggest online industries would appear to make commercial sense, though I can imagine the complications of regulatory compliance. Hard enough for one or the other.
Thia casino isn't a true Bitcoin casino either, since you sti have to withdraw in fiat. Pass.