First try doing this, here is step by step of what I did.

Started 1st stage upgrade, waited near the right geyser and face melted the enemies, ophelia flew down so I flew away, flew back and killed the 1 ranged enemy.

Started 2nd stage upgrade, went to right geyser again and face melted what I could and ran away.

With 2nd stage upgrade I got a pack of roadies, once they spawned I did the double up attack and walked all the way on the left side to the enemy stage while the other 2 roadies followed behind.

Once at the enemy stage mash the double up attack and then win. The double up attack knocks Ophelia back so she does bugger all.

Hope this helps as this mission is ass.

Credit to this post https://www.xboxachievements.com/forum/topic/172068-brutal-tip-being-really-really-cheap-for-the-win/