I don't think it is a pocketdice.io clone, it brings something new to the table with a Russian Roulette game, which I found very interesting and cool.
Open both sites next to each other. It is an obvious clone despite making it "russian roulette" instead of dice. Obviously the code is different. It's about the ui+visual design/provably fair method/text/etc.
Anyway, that's their choice. It just looks always cheap to me and therefor more sketchy. Although I don't trust most new sites anyway.
It also does have a way to verify if bets are provably fair, so I don't know where you're getting your info from.
Just because there is a way to verify some hash, doesn't mean it is provably fair. See this topic from 1+ year ago:
https://bitcointalk.org/index.php?topic=1077905.0 I also made a more simple explanation here:
https://bitcointalk.org/index.php?topic=703265.msg15115541#msg15115541 Both PocketDice and BitPistol are not really provably fair. PocketDice also
acknowledges this and is planning to add a better provably fair implementation "soon".