Whenever you start a calculation with a nonmagnetic starting density the result will also stay nonmagnetic. In such a situation it does not matter whether you perform the calculation with jspins=1 or jspins=2. This means that you have to indicate the magnetic configuration you are interested in to the starting density generator. This is done by specifying magnetic moments at each atom (or at least at one atom) in your unit cell. Specifying magnetic moments is done by modifying the electronConfiguration of the related atomSpecies in the inp.xml file. If you inspect your inp.xml file you will see that the occupations of the atomic states is symmetrical with respect to spin up and spin down electrons. Just shift some spin-down electrons to spin-up electrons and you will get an initial magnetic moment.

In your case you are probably interested in putting a magnetic moment on the Vanadium atoms. The relevant states here are the 3d3/2 and 3d5/2 valence states. The 3d3/2 states offer place for up to 2 spin-up electrons (and 2 spin-down electrons. The 3d5/2 states offer place for 3 spin-up (and 3 spin-down) electrons. Overall there should be 3 electrons in the d states of Vanadium. I don't know what final magnetic moment to expect in the systems you investigate. In general I would put a slightly larger initial magnetic moment on the atoms than what I would expect for the final magnetic moment. If the initial magnetic moment is too small there is a chance lose it and end up in a nonmagnetic solution. I would thus put all 3 Vanadium d electrons in the spin-up channel: 1.2 in the 3d3/2 states and 1.8 in the 3d5/2 states.