Win a match on Dig site and this achievement will pop. Easy as that.
Side notes:
After recently boosting Titanfall (Xbone) in the Japan West servers.
We've been able to start games with just 2 on each side. So if you can get four people together, you'll be able to smash through most of the Frontier's Edge achievements. The easiest way to do this is to get two people who can connect to each other (Taking into account people's NAT types). Then have both these individuals set their server's to Japan West.
This trick will help as the Japan West servers are virtually only used by Boosters. So you can go into either Frontier's edge Attrition or Variety Pack. Once both teams find each other, you can continue to play at your own leisure. Then work on the achievements at your own pace.
Any questions, feel free to message me.