[edit: cross-posted with LK! His advice stands, this is just detailed and shows an alternate method of wiring, considering that you've already shielded]
OK, dude, here's a bit of help. I'll post the diagram first, and then an explanation of what's going on:
1. EVERY part of the foil-covered part of the cavity must be electrically continuous with itself. I should be able to send a current from one end of the foil to the other. If you need to test this, you could get yourself a cheap multimeter. Otherwise you can just trust yourself or do some tom-foolery with a battery and a small bulb.
2. For the following diagram to work, the pots' shells MUST touch the foil shielding. This "adds" them to the continuous shielded circuit. What's more, the 'bare' wire from the pickups isn't actually a true conducting ground, it's just more 'shielding', so you can solder it directly to the foil and thereby "add" it to the foil shielding. So in theory, I should be able to touch the back of one pot with one multimeter probe, and the braided wire of either pickup with the other, and get a circuit.
3. The switch isn't really all that important in terms of grounding, but if its shell is touching the foil, you're set. If it's made so that it's NOT grounded directly to the foil, and there's a special "lug" for the ground, then just solder one end of a short wire to the lug and the other end to any handy space on the foil.
4. No matter what diagram you look at, the fact is that all grounds will end up at one place-- ground. Any fancy ground wiring like from pot-to-pot or whatever is just a way of getting them all to ground. Done wrong, though, it can create ground loops. So instead of wiring a bunch of wires to the pots, you will treat each ground as a separate "path". Even the lugs on your volume knobs that are bent back to touch the pots, DE-solder them and bend them away from the pot. They will eventually have wires on them, too.
5. In the diagram, all grounds are indicated by that funny arrow. True ground and the "cavity ground" are not the same thing. Assume that the cavity foil + the pot shells + the switch are just one giant "object", and they too must be grounded. That's the wire coming off the Bridge Volume pot. It's the only solitary wire that comes "out" of the cavity shielding, and it also has to go to ground. This is the step I forgot when I did it. Adding this wire in cleared everything up.
6. So, the bottom left "ground" arrow symbol represents all the grounds coming off the 4 pots' lugs, the 1 pot's shell, and the 2 pickups. I then show all 7 wires attaching to a central spot-- this can be a washer or an O-terminal or a copper penny or whatever you want. Then the final wire attaches to the output jack's ground lug. The one and only true ground point.
7. That O-ring or washer is called the "star" for obvious reasons. ALL of your grounds go here! Once you've soldered them all in place, wrap some electrical tape around the star and make sure no bare wires are touching the foil shielding. Why? Then you have ground loops all over again!