I am Ps2cho's father, and trying to help from afar...
We resealed the rear pump, but here is what I read about the function of the rear pump, I dont think its related.

Secondary Pump:
Secondary pump is required only for towing and tow-starting
vehicle. It is designed as an external gear pump and is positioned in
rear section of the transmission. If needed, secondary pump is driven
by centrifugal governor shaft. Secondary pump operates only if engine
is not running and vehicle is rolling (tow-starting procedure), while
brake band B-2 slowly engages. Pump stops operating when vehicle comes
to a stop or if transmission has shifted into 4th or 5th gear (engine
running).

However, we also resealed the Kickdown Solenoid.
We took it out, replaced the 3 "O" rings, and replaced it.

Here is what it says, and what he is experiencing...

WILL NOT UPSHIFT
Incorrect governor pressure. Defective governor assembly.
Check for stuck kickdown solenoid or for constant voltage to solenoid
caused by a defective fuel pump relay or sticking kickdown switch.
Valve body dirty or valves sticking. Repair or replace valve body.

If we did something wrong with the Solenoid, would this make sense?

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2009 Mercedes ML320 Bluetec