Jagunmolu I have seen the agreement between VK and the Federal Government. It exists, it is unambiguous, and it is signed.
I don't think VK has a problem (though I don't know this for a fact) with other airlines using MMIA as a hub. VK and Arik are using it now so why not other airlines as well providing there is space available on the stands and in the check-in area. The existing operators should have grandfather rights on the flight scheds and pier positions, but if that isn't an issue then open the hub up to more. In theory this increases passenger throughput which would benefit everyone.