I extended the jack that was 'stuck' (and then unstuck) when I got to my current RV park. The morning after arriving, I had to move the rig to a new spot to avoid some construction work going on in the park and darned if this time it didn't retract as fast as the others.
So I think that the problem solved itself for now. And I got myself a 6 foot long lever (2X4) to carry with me too, along with my floor jack. This will give me the time to try to find a new valve since there's no hurry on that part of the issue.
Thanks for everyone's advice...especially Doug's. Nothing like having a RV tech on the forum.