Could it be wind damage? As the only leaves that look affected are older leaves that may have been bashed about by that hurricane/storm a few weeks back. New growth looks fine. Soft lush growth can almost get desiccated by very strong winds, get de-waxed and then bruised by the soil. Some of our OSR had what appeared to be spray damage, yet had not been sprayed, some softer large cotyledons crisped up completely, all recovered now.