To obtain the result, you need four things:
1) BetID: You can obtain this from your "My Bets" column.
2) No. of challenges: Number of challenges issued to opponent.
3) Total Bets: This is the total PVP games played by user, this can be obtained from the "Profile Settings" page on the top left corner of the page. Please note this must be your total bets at the time of the game; not to be confused with your current Total Bets.
4) SEED: This is automatically generated by the server, although you may change it whenever you like; found on the top left corner of the page next to the logout button.
Steps to obtain a user's roll number:
1) Combine (1#2#3#4) in sequence.
I don't understand your provably fair method at all. It seems the 4 variables to calculate the roll outcome are known to the player in advance. This would mean the player can generate their own results in advance and therefor cheat.
BET ID is a randomly generated number which is our 'variable' in the provably fair concept.
I would like to try your site, but it seems no one is online.

Please note there is a 0.001% fee to all CashOuts by PvPDice.com, this is equivalent to $1 fee for a $1,000 deposit.
Is the fee 0.001% (you take $1 for a $100,000 deposit) or 0.1% (you take $1 for a $1,000 deposit)?
The fee for both is 0.001%
As noted the site says:
$1 fee for a $1,000 deposit. That is 0.1% not 0.001%. So which one is it? Just a fee on wagered/profit amount would be better IMO.
0.01% of $1,000 is $10
The idea was to encourage more betting on a platform far more fair than others, a true game of chance if you will - we always knew the community wouldn't adopt it as quickly as other games such as SatoshiDice, JustDice or PrimeDice which is another reason the fees are so low.
The planning of this project has gone into immense depth and believe it or not this whole launch is more of a proof of concept than a claim to profit, if it fails the plan was to always scrap it and move on to other ventures (Bitcoin related) however if it succeeds then we will take it to the next level (involving a much larger level of commitment from the team and financial investment).