The quick answer is no, you cannot hook up a Scott Pack to a paintball gun. They are not made for that. The 100psi output from a pack is not enough for most paintball guns. You need at least 800psi to properly operate most guns for interchangability with CO2. A scott regulator will also not have enough air flow to properly charge up a gun to maintain shot to shot consistency.
A quick charge whip is a hose that connects from an unregulated bottle on-off valve that allows you to connect to the fill nipple on the gun bottle.
Any paintball store or online paintball store should have the fill nipples needed. You won't need a nipple if you have the proper bottle setup. It will already have one.
You need a proper paintball tank with regulator to properly and safely operate a paintball gun. Don't try to jury rig a setup without proper high pressure air knowledge. It is very dangerous and can kill or maim.
Except for the Automag in front, its usually the man behind the equipment that counts.