[2021] Is it just me, or is the industrial sabotage mission ridiculously difficult?

I've tried it at haz 4 a couple times now, I'm player level 286, playing with friends around 100. We can't figure out how to deal with the boss fight. The robotic appendages do really really high damage and are really tanky, and the melee attacks are impossible to dodge and penetrate terrain. The shields it spits out lets you get screwed over by the tentacles while you can't hit them. If we stay safe from them (guerilla warfare from tunnels), we go so slowly through the fight that we really struggle for ammo. How are you supposed to deal with it?