Yes and No. It all depends on sand condition and where you try. If I were you I'd stay on more solid ground by the Roll Over Pass. They do have two VERY EXPENSIVE tow companies that harvest RV's off the sand if you choose to gamble.

You should be fine. The beach is wide, long and hard packed. There were other very large 5th wheels when we were there. Police patrol regularly. We travel in a 24 ft RV and loved it there.