Rear is fed by the reservoir on the front/right side of car. Front left is for headlamp washer if applicable. There’s only a single pump which can pump in both directions for both front and rear washing. It reverses polarity depending on where you choose to wash.

Assuming there’s washer fluid in the reservoir, then yes, a clogged nozzle is a possibility. It’s a fairly common issue remedied by removing the rear wiper arm and inserting (with fingers) a drill bit (3/32” maybe, 1/16”? I forget... the biggest that will fit into the hole) into the metal fluid outlet fitting and spinning clockwise (again, with fingers) to clear the clog.