set another CDMA operator in a verizon wireless galaxy tab
Generally speaking, rooting is completely unrelated to unlocking.

CDMA unlocking is also more difficult than SIM unlocking a GSM phone, and CDMA phones need to be activated on the network, unlike sticking a SIM in an unlocked GSM phone and doing whatever you want.  You'll need help from both carriers (Verizon to unlock, your carrier to activate) in order to do this.