In theory, for the FN family NUCs, you should be able to connect this monitor to either the USB-C or HDMI connectors and (by my finger math) achieve a 120Hz frequency (aside: if you are going to use the HDMI connector, make sure your HDMI firmware is up-to-date).
I must mention some provisos, however. First, people have reported issues using Intel HD Graphics with ultra-wide monitors. Usually these are with respect to the 5120x1440 DQHD monitors, but I caution you of the possibility anyway. Second, my finger math may be off and 120Hz is actually not achievable. In this case, you might end up at 85Hz or 75Hz. Third, through some artificial limitation that I don't know about, you might get limited to 60Hz (hopefully this is just my pessimism coming out).
DP 1.2 is a natural subset of DP 1.4, so this isn't a factor (per se). My provisos above talk about the possibilities for the result being limited by the fact that only DP 1.2 is available.
Hope this helps,