Does this Walmart allow RV parking overnight?

Yes

Yep

Yup

As an update to the question, they may be RV friendly but approached us after we were parked there for approximately 18 hours in a Skoolie and told us we had to leave because we had been there for over 48 hours. When corrected, politely, they just kind of shrugged it off and told us we still needed to leave still. So Skoolie friendly for enough time to sleep maybe. (we were not a nuisance in any way while here.)