I see he changed minimum and maximum bet amount so it may be an update?
Max bet was unlimited earlier, when he was asked to provide cold storage address, showing that he has the funds, it's when he decided to change that and he didn't change it in the previous thread, he deleted it and then created another, so that the questions involving that gets buried with that thread.
why it is scam?
The OP explains all that but I'll give you an example how the missing provable fairness system can be used by the owners to manipulate the results and scam the users.
There are 10 numbers you can bet on, 1 2 3 4 5 6 7 8 9 10 and one is declared winner by the site and that people who have chosen that number get 10x their bet but there is no way shown how the number is picked and this is where site can manipulate it. For ex.
Let's say numbers:
1 has 1 BTC bet
2 has 1.5 BTC bet
3 has 1 BTC bet
4 has 2 BTC bet
5 has 0.2 BTC bet
6 has 0.5 BTC bet
7 has 4 BTC bet
8 has 2 BTC bet
9 has 0.8 BTC bet
10 has 1.2 BTC bet
In a round, the total bets received by the site is 14.2 BTC, now the round ends and the site has to declare a winning number, they know which number has received how many bets, so they declare the winning number '5' which has 0.2 BTC bet, the bets get multiplied by 10 which is 2 BTC and it gets distributed to the betters in proportion of their bets.
14.2 - 2 = 12.2 BTC profit to the site, this is why they're not taking any percentage, because they know they'll always declare the winning number with the lowest number of bets.
This is why it's a scam, and this is what it was asked in their previous thread that how will they choose the winning number, they didn't had any answer and then they buried the thread.
Hope you understand it now.