I would have that looked at by an RV shop or even mobile repair person. Mine don't look that way at all and I'd be afraid the floor has separated from the wall for whatever reason.
While in Houston for an extended stay, I observed several mobile techs. replacing a floor on a slide out in an adjacent spot. It took several days and they constructed a make shift tent over the job as it rained several times.
2009 Duramax w/Transfer Flow Fuel Tank
2017 Rockwood Windjammer 3029
Almost South of the Border