The proof will be stunna's statement that he will be posting how the exploit was done, Stunna of all people who actually let him to withdraw 2k + BTC wouldnt even lie about this, if he was legit, Stunna will get over with this since this is a good promotion for the sites to prove that PrimeDice is legit, but his statement of he will be posting the details explanation is indeed another proof that hufflepuff was indeed cheated

Although there is still no explanation yet from stunna, but it will come eventually