With the relays and the (celery) control stick removed; you have ruled out the water pump as a source of the fault... and a few other things too.
With the relays and the control stick removed; you have NOT ruled out the wiper motor or some of the wiring going to the wiper motor. The motor has one rogue wire that has a direct connection to Fuse 55.
The next thing I would suggest is to remove (or partially remove) the plastic cowling that surrounds the windshield wiper arms. With the cowling removed you can electrically disconnect the wiper motor, and do your fuse test again. While inside this area, do a good visual inspection of the wiring harness, look for wire damage anywhere, everywhere.
I need to remind you that the troubleshooting method you are using has been done millions of times by many others; but many people do similar work while also using a multimeter (DVM). The "load side" of fuse 55 is likely shorted to ground/chassis/car frame and it should not be.
Edit: The cowling has two halves. It may not be the cowling that surrounds the wiper arms; it might be the one on the opposite side of the car. Also, reminder, I am using a 2002 diagram that shows this same system, but it is fed from F56 not F55.