Here's an excellent blog about dead camera problems:
http://camerarepair.blogspot.com/2007/11/simple-fix-for-dead-cameras-that-wont.html
Aside from severe oxidation on the internal battery contacts, or power switch, there's also the possibility, as you suspect, that the power feed circuit might be bad. Wish I could help you there, but cannot come up with a schematic, and unless you can find a shop that might have one, I doubt you'll get any help from Olympus, due to the item's age. Guess you've called around to the local shops, but that might be a lead, if you haven't tried already.
As far as the flash is concerned, you can charge up the flash capacitor while you're in there, and check it- it and the xenon bulb are the most suspect components to fail in that circuit, aside from the step-up coil, and you can ohm it out, although it still can be shorted unless you know the coils resistance.
I bought a Camedia Polaroid model in 2002, and it still works, however, I get a slightly grayish screen when I power it up. If I give the camera body a solid WHACK with my hand, it works. This, obviously, is a mechanical problem, but I bought a better one, so haven't investigated the problem. Probably not the same problem you're having, but just throwing it in...
I've never seen a fuse in any cameras I disassembled (a few Olympus), but if they have a fuse type component, I would suspect a FL (fusible link). They're usually around 1 ohm, and serve as current overload protection.
I would suspect a device of this type, if any, since the voltage is low, as well as current. There may be none.
Hope you find that schematic- it's tough to trace stuff out without one.
Good luck, hope something here helps...