Tech came back with new wiper. Looks identical to the old one, Nothing was missing compared to the old one like he said was missing.
Replaced the old one and declared it "fixed". I tried it, and the spray pattern was the same.
I must have been imagining it. But I was sure the spray wasn't working right, and apparently the tech did too.
He left, leaving the big plastic inside cover laying on the ground... Nice touch.
Clearly this guy had no idea what he was doing. Oh well, no cost to me and a free new wiper and blade.