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Only 15" 2009 have that problem. 13" are unaffected by the cap plague. If 1.05v is present on C7771, you will have to start looking elsewhere.
Does PM_SLP_S4_L go up to 3.3v when you press power button? Do the rest of the power rails in the machine work? There's a lot more here than JUST PPBUS_G3H!
Voltage on pin 5 of U6901? Is it possible to power it on in SMC bypass mode? Remove power and battery, press power button and insert AC adapter, keep holding power button for another 5 seconds. Release it and press it again.