No fluid from right rear brake line

Had the owner of the 01 GT come over today so he could help me bleed the brakes. Backstory, I had to remove the 4 lines from the top of the ABS module in order to install a new fuel line (feed side). Nothing is leaking fluid anywhere.

Started at the right rear as usual and noticed I wasn't getting anything. Pulled the banjo bolt and cleaned it out. Still nothing. Left the line off the caliper and had him press the pedal gently. Nothing more than a drop or 2. For a test I undid the left rear and repeated. Fluid shot out like it should.

Installed a new brake hose on the right rear and STILL nothing more than a drop. I'm not sure what else could cause this other than maybe the aluminum proportioning valve that is right before the brake hose on that side.

Anyone else have a better idea before I replace that valve?

So much for a 1 hour brake bleed....

on a different make and model, i had this problem. someone much smarter than me on brakes said bleed the fronts. that can help to reset the valve. it worked on that one.
sometimes hammering the brake pedal a jillion times helps.
sometimes gravity bleeding can help.

Well, I can always try the fronts first and go from there.