So I was wondering, since we now have the dice rolling and RNG are we able to make user made casinos ? If so, where would one post that at?

I'd say Charity, if they win prizes for dice rolls.
Unless you intend for them to pay for it?

Ah.
Either hangout or arcade then.
I'd say hangout.
Others might say arcade, but even if it's technically a game, I don't feel like it fits with the others things posted in arcade.

I would think of it more like: "this is a hangout, with some friendly betting on the side."

Though, it depends on if staff even would allow it.
I don't see them having a problem with it, as long as long as everyone is agreed.
And it's not as if you can skew the dice rolling to benefit yourself.

I sent the thread to Cookie on Discord. They're the policy manager, so they should know if it's permissible.
If not, they'll probably consult with Fozzy or Qt about it.