No. There is only one
relief valve for each
"jack" or "room".
So if your RVA pump looks like the one in the photo which has three "pairs" of solenoids (a pair consists of an Extend and a Retract solenoid) for three leveling jacks, then you must have another pump somewhere under the Coach for the Room Slides.
My Coach uses the RVA II system. Maybe you have the RVA 1 system. I'm not familiar with that one, but I'll see if can find something on it on the internet.
EDIT: Here is the link to the RVA website. https://www.rvajack.com/ I looked over the manuals for both type systems - but there is no mention of RVA being used for the Room Slideouts too. Are you sure you don't have another pump for the rooms?
Worse case, you could crack the hydraulic line going to the (each) Slide Room so the oil comes out when you push the room in - but that would make a mess and be a last resort.