Ocean Monument Grey Screen Crash

While navigating a water temple in a locally hosted server with another friend, we had played the entire "game". Making it to The End and killing the dragon, etc. When attempting to navigate and explore the new water structure, we were both met with the same crash. Grey screen and then the loading client restarting itself. This occurred about three separate times for each of us before we moved into creative mode and flew away from the area. No other occurrences happened except for in the structure. These occurrences were not at the same time, we both crashed at separate times during our time exploring.