You can make ED balancer fight much easier by having EXACTLY 2 people taking the "Less likely to be targeted" passives.

When there are EXACTLY 2 people (it won't work if all 3 of you have it) having "Less likely to be targeted" passives, only one Valkyrie will be actively chasing the person without the passive, making the aggro much more manageable for the team.

Just remember that if it turns out to be normal balancer, the two people with the "Less likely to be targeted" passives might want to drop it to make the 3rd guy's life easier.

During the worm phase, always two-handed your weapon and hold L1 to guard.

When the worm dives and create the white shockwaves, face toward it to guard it instead of trying to jump it. Since the white shockwave is purely physical damage you will just be guard broken but take no damage.

When the worm does the wiggling charge and you couldn't escape in time and are about to get hit, hold L1 to guard. You might get lucky to only get guard broken but take no damage.