Working on it. Will try to capture video and test multiple environments. Might have results in tomorrow
mob griefing only stops mobs from affecting blocks. Sheep won't destroy eaten grass, and Creepers won't explode a hole in the ground. However, this does not prevent them from killing other mobs.
Hope this helps 😉
You asked for the level.dat file, here it is!
Oh... it would be cool if it did something... still helpful to know you can /setblock it.
https://drive.google.com/file/d/0B9bR1J5CF8nCNnM4WWhuZHlQeVU/view?usp=drivesdk