Not many knowledgeable slide out techs on this forum anymore. Two good ones are no longer active here.
My thought on motor side needing adjustment. If motor side seals properly, slide in/slide out, that side should be okay. Motor side has a stop can, to stop, and adjusting lock nuts when going the other way.
If the non-motorized side is not sealing in or out (one or other) by 1/2", there are a couple bolts on my similar slide arm to loosen, and push slide in/out, to adjust, whichever is needed.
On mine for horizontal adjust, there are two bolts each side to loosen, push slide, retighten when clearance is satisfactory.
Jerry