You don't actually have to hit Gold; either the trophy description is wrong or the trophy itself is bugged, but me and my friend both earned this trophy while only hitting Silver III during Void Edge (Y5S1). My exact MMR when I unlocked the trophy was 2335.
To actually rank up high enough to earn the trophy, play your best, communicate, and try and keep a positive attitude. Good aim helps a lot, but positioning is key. Use your operators' utility to its fullest extent. Don't forget to drone when attacking, and don't forget to reinforce important walls on the bomb sites.