We had rollers installed on the full wall slide of our 2015 360 RB Legacy to prevent the slide from scraping the floor when retracted. The rollers appear to be the same as yours. I have a thread with pictures in another thread on this forum. Some of the rollers do not contact the floor when the slide is extended, but all do when retracted. Our rollers appear installed the same as yours. I don't see how the frame on our rollers could scrape the floor -- the roller will always contact the floor first. Maybe check to see if the rollers actually turn and that the bolts holding the brackets to the slide floor have not loosened. Also, check to see if there is anything caught under the slide floor -- we we bought our Legacy, we found an assortment of pieces of wood and screws there.
2015 Legacy 360RB with 2013 CRV toad. Retired USAF.