Is there any benefit to using twisted pair for short-distance I2C?
If you follow a proper EMI concept, then nothing speaks against connecting two devices over I2C. 

Yes, you should use a twisted pair cable, as this is the weapon of choice against inductive coupling. If you use a shielded cable, you can suppress capacitive coupling, too (You must connect both ends of the shield, but beware of ground loops).

You can do even better if you isolate the I2C transceiver at one end.