Michael,
I just got to this forum and thread. Your '07 Journey is not all that different from our '04 Itasca Horizon 36GD with the CAT C-7 330HP in that, you more than likely have an HWH slide/leveling system and, it's also more than likely the 325 system or on a remote possibility, a 625 system. The prime difference between the two systems is, the 325 system is a manual leveling system and the 625 is an Automatic leveling system. But hydraulically, they operate the same.
Now, I'm only assuming some things here but, is your bedroom slide a "closet" slide or a "Bed" slide? A good buddy of mine just recently had the almost same exact experience you're having and it turned out to be just what I thought it might be. And that is, it was the "Shuttle Valve" that's located in the top section of the manifold/pump assembly, right under your entry steps of your coach. If you run your fingers under the front lips of each step, you'll run into a nut protruding downward about mid way. That nut is what secures the step cover from rising on it's own. That would be pretty tough anyways because they're a bit heavy.
There's a nut on all the step covers. If you remove that nut, you'll be able to lift the step and it will hinge backwards and you'll then see the entire HWH pump and manifold assembly. One of the first things that sticks out on that assembly is a U-shaped component right on top. Under that U-shaped item, resides the shuttle valve. It's a valve that's about the size of a long spark plug and about the same diameter. It's job is to allow the pump to pick up oil from the reservoir and then pump it to the appropriate solenoid that's being asked to open or close, based on operation desired. If that shuttle valve fails, the pump can run all day but it won't be pumping any hydraulic oil because the shuttle valve is no longer allowing it to.
Your symptoms are quite typical of a bad shuttle valve but, this is not guaranteed. Shuttle valves can be had on-line from various sources or HWH directly. They're not all that expensive, around $75-$100, depending on where you purchase it from.
Scott