Toyvet,
I have never heard of epoxy based paver sand, but if it can stain the pavers it's probably the culprit. As far as sealing my suggestion is NOT to seal. First reason, if there are stains then the stains will be sealed there too. Second it will more than likely change the color of the paver. Third the efflouresence that takes place could prevent that from happening or just start breaking down the sealer.
IF it is an issue of preventing stains from bbq's and dirt you're better off to use a cleaning solution every couple of years.
Once you've put that sealer on you're committed.
However if you're going to do it then the best place to go to find a sealer is at your local concrete supplier, they have lots of professional cleaners and sealers.
Good luck!

you could try using muriatic acid to clean it up but be careful. It is highly corrosive and will burn anything organic that it touches including skin. wear rubber gloves and eye protection. 1 part acid to 10 parts water to dilute it. add the acid to the water, not the other way around or it will give off nasty fumes. scrub the stained area with the diluted acid, let sit a few moments and then hose off with plenty of water to nutralize the acid. good luck