Whether the Department can also file an appeal before the Tribunal against the orders of Appellate Authority or review authority

Yes. The department could also prefer an appeal before the Hon’ble Tribunal in FORM GST APL-07. The procedure is detailed below:
 The Commissioner may, on his own motion, or upon request from the
Commissioner of State tax or Commissioner of Union territory tax, call for and
examine the record of any order passed by the Appellate Authority or the
Revisional Authority under this Act or the State Goods and Services Tax Act or
the Union Territory Goods and Services Tax Act for the purpose of satisfying
himself as to the legality or propriety of the said order and
 He may, by order, direct any officer subordinate to him to apply to the Appellate Tribunal within six months from the date on which the said order has been passed for determination of such points arising out of the said order as may be specified by the Commissioner in his order.

(ICAI FAQ PUBLICATIONS 06-09-2017 Appeals to the Appellate Tribunal: FAQ NO. 43)