For static management on UV printers I usually reccomend people to spray the material down with 90% or better IPA, spray it from a spray bottle like you are cleaning glass and wipe it clean with a lint free mircofiber wipe. I've also seen people get good results with the "static string" from stopstatic.com, it is a tinsel embedded elastic with grounding magnets on the ends. It's pretty cheap, and low tech but it does work.
You can also spray static guard or similar products directly on the media, as long as you do not apply it to the point of puddles, I have not seen any issues with it for staining the boards or adhesion loss.
Last ditch, lower your head height, and carriage speed of your printer allows this. That should reduce the amount of suspended ink mist lingering in the air for the static charge to attract in the first place.