1> Pulakesi spoke Prakrit, at that time Prakrit was the spoken language and Marathi was inherited over the centuries from Prakrit. So no point in denying Pulkeshi as not a Maharashtrian.
2> Satawahanas and King Shalivahan of Paithan is only and only a Maharashtrian. Well just for information the North India follwos the Vikram Samvatsara and Maharashtra follwos the Shalivahan Samvatsara or Hindu Calender.