So, on the start up sequence.
Yous the US version without heat exchanger, so slightly different than the EU version, but I should still have that adapted version in mind.
The machine runs the drain pump until it sense the sump is empty plus a timed period.
If it senses water level isn't low enough, cycle will be ended with a drain fault code.
One of the 2 fault codes you mentioned links to a blocked drain pump - but that's not what your issue sounds like.
Then the machine runs the wash pump calibration. The wash pump is run at varying speeds for a couple seconds each.
If the calibration values are far out of range, cycle would be aborted with an error code.
Then the machine opens the water valve for a few seconds until the flow meter registers any impulses.
If the flow meter registers any impulses, the machine knows the water supply is on.
If not, the cycle is ended immediately with a fill error.
If not, the fill sequence should start.
Given you don't get the characteristical fault codes with these machines (a blocked drain pump, a wash pump fault or a no fill error), this could be one of the weirder errors.
The fill valve checks out fine from what you say by my estimation.
The flow sensor is only a 20$ part and might be worth a try.
However, if that doesn't help, the control module sould be my next guess - which is 230+$ part.
Checking all the wiring and connections is always cheap insurance.
If the service comes out for the recall anyway might be worth letting them just do that and while they are out ask them for any advice.
Along the lines of "I called for the recall and haven't used it since" or such.
