Rollin.io has actually been closed since 2017, and there hasn’t been any report about a new site. But I checked their Bitcointalk account, and it was still active last month, so maybe they’re just visiting the forum from time to time.

As for Safedice, it’s already known as a scam casino. Even if they launch a new site, I doubt it will become popular because of their bad reputation. In fact, you can still access safedice.com, but if you try to deposit, don’t bother, you won’t be able to withdraw anything.