you might be able to alleviate the situation by cutting a reglet into the mortar joint then insert a rubber membrane extending to the top of the sidewalk retaining wall. any rainfall now soaks the soil - water runs downhill hence into your very fine home.
didn't bother looking at the video as i hate them but imagine its the perforated pvc drainage pipe to collect the leaking water then direct it downhill to daylight drainage. we normally use an exterior sump & pump - its faster, less expensive, & more permanent for our clients.
IF it were our home, i'd use membrane as we're selling w/i a year :-)