So after about 4 hours my fireteam finally defeated skolas. And no it wasn't with the fourth horsemen or with perfect sniper headshots. Let me tell you how we did it and hopefully it will help you finish this too.
We started the match running to the back left corner and popping a bubble with weapons of light. You want to have a titan with helm of St. 14 and pop the bubble in front of the door where the severtor comes out. This made any other ads that came out blind and unable to shoot us right away. We then Sniper shot skolas with patience and time (we used p&t because of its high stability and large magizine size and 25 rounds available) until the bond was broken and the mines started to show up.
This is the tricky part because we couldn't take him down fast enough to ignore the mines. We left that area and went for the mines right away only shooting ads that posed a threat. This part is more about luck than anything since you can die quickly from arc burn.
After the last mine was dismantled we focused fire on skolas again until the next set of mines spawned in. The we repeated the previous step, dismantling all mines until they were no longer an issue.
After dismantling the last wave of mines we focused fire on skolas until he was dead.
Try this strategy if no other strategy works for you. It takes time a lot of time and patience. We breezed through the first 5 rounds with no issues or wipes until we got to skolas... but eventually took him down.
Overview:
-run left
-pop bubble with st. 14 and weapons in front of door where severtor spawns.
-shoot Skolas with patience and time getting as many headshots as you can. Break the bond and summon the first wave of mines
-dismantle mines
-focus fire on skolas until the second wave of mines spawn in
-dismantle mines
-focus fire on skolas until he is dead.
P.S.- don't forget about the essence debuff that last 30 seconds and if not passed to another player you will die.
P.S.S.- We did it without any hunters to go invisible for mines but with a hunter the mines could be much easier.
This was not easy nor was it intended to be so be patient and take your time. Hope this helped. I will do my best to answer any questions you guys might have.