Jesus. How did you get past the first area where Dinklebot has to decrypt the gate?
Video:
https://www.youtube.com/watch?v=J2ivRvW1qys
My char after getting those last 3 strange coins! (Was level 23 during the strike)
So going to write this here just for the sake of anyone wanting to try, it's the safest method I could come up with.
Mesh hacking zone
As soon as you deploy your ghost to hack the terminal/computer thing, run left towards the entrance to the hive cave, and jump over the fuel tanker thing, from here pick off as many enemies as you can, walking around the left side and jumping on top of the fuel tank closer to the little arena area when needed, a fusion rifle works extremely well against the fallen captains, cuts their shield away for fun.
Once you get it to 2/3 your ghost will mention that more fallen and now hive are coming - HIDE, right at the back where you first ran to, just sit tight and peek now and then, let them fight each other until one side is completely victorious, then again pick off the stragglers, continue this until it says 3/3 and you're able to push on to the next area.
Walker
So my technique here is to enter the arena, and cling to the left wall, and follow it all the way around the left side until you encounter some fallen and dregs, pick them off while still pushing forward and you should be able to slip in to the building to the left of the walker, theres stairs going up here, take them.
All you do then is peek out and pick off the dregs/fallen and switch to fusion rifle whenever a fallen captain appears, be mindful of dreg grenades.
Rather than do the usual attacking of its legs (though you may have to depending on skillset) i simply logged grenades at the walker, then tucked safely back half way up the stairs and went off of the sound to tell when the walker had dropped and exposed its neck - for me since the grenades were doing so much damage, it made more sense to pick off the stragglers and the sniping fallen while the tank was out of action.
Sepiks prime
Basically as I did in the video, remember to switch to fusion rifle whenever a fallen captain comes running in.