Regardless if Hillary becomes president or not she would have no say so on any Article V COS. It is called by 2/3 of the states and amendments are proposed. Those that receive enough votes then move on through the regular amendment process with each amendment requiring that be approved by the state legislature or state convention and if 3/4 of the states pass them they are ratified and become part of the constitution.
The President veto power cannot be used to stop an amendment.
I agree that she would have no legal say in the issue. But I can see her using all sorts of tricks and pressure to prevent the necessary 2/3 of the states from meeting. Bribes, threats, promises...anything is possible with her.
Hey governor, nice little army base you've got there in your state. Be a shame if it got closed.