How could mercutio been responseable for the death of romeo and juliet?

Mercutio could have been responsible for Romeo and Juliet's death because if he hadn't stepped in when Romeo didn't want to fight Tybalt (even though Mercutio did it to save Romeo's reputation) no one would have died so Romeo could not have been banished therefore allowing Romeo and Juliet to be together.

The details about the statues, i believe, are that they're carved from blocks of igneous stone, many of them are partially buried under the ground which to preserve and protect them from the harsh environment on easter island, and many of the facial features have washed away. also, the most well-preserved one is at the british museum in london.these are just guesses from what i can see and what i think i read correctly. i'm sorry i couldn't be more .