After posting I opened my eyes and realized the obvious: there's a metal frame at the top front of the washing machine (behind the control panel) which can be removed with 4 screws! This allowed me to attach the water valve first, then have enough room to (firmly but carefully) push the water distributor forward and attach it to the water valve. Pictures say more than words, so see below.
As you can see, I also disconnected the cable from the front control panel (buttons, display etc.) which wasn't easy and could possibly risk damaging the cable/plug. In hindsight I could probably j