By sharing a party with the Bolsheviks, they made the Bolshies more palatable.

I am not sure they did, I think everyone was able to distinguish between the two. Under the mid-Kerensky government (pre Kornilov), the Bolsheviks were outlawed, but (IIRC) there were two Menshevik ministers, or at least the Mensheviks supported the government.

They are guilty.

Of what? That they - along with the Kadets and many other forces, including the tsar - can be blamed for the rise of the Bolsheviks is absolutely true.