No crank No Power

[rreffell]

So a few months ago my dash started throwing random lights that would go away (yes I am a piece of S***). Then all of a sudden my trunk stopped closing with the press of the button on door. The intermittent lights became worse and a week ago my car did not start after a crazy rainstorm. The vehicle was completely dead. No lights, no electrical components humming NOTHING. I was able to use manual lever to put it in neutral and I had my baby towed home. After trying to jump it again I realized the battery was dead. After charging my AGM battery I reconnected it only to have the same no power issue. Battery voltage was 12.7v at lugs. I then discovered there was an inch of water in boot area and the trunk control module area on passenger side was under 2 inches of water. I removed about 3 gallons of water from the boot area and passenger rear area and let it dry. I ordered another trunk module and am waiting for it to come in. Checked all power distribution fuses and they are all ringing good. Still have no power and am starting to believe the IBS is not functioning. When I connect the battery to terminals and check voltage I am getting 4.7v from battery + to -. Can anyone shed some light or has this happened to someone in the past?