Wall on Lupicus
Well, from what I know Wall should be slightly aside from the center of the red circle, facing the Lupicus.
your whole party has to be stacked in the middle of the wall; otherwise, the targeted AOE component of the frenzied blast will not be reflected and you will miss out on a lot of damage.
if I’m not wrong it doesn’t necessarily have to be in the exact centre though, you just have to be in the hitbox of the wall itself (the small line in the centre). you can be standing on the right/left of the wall and still reflect damage.
there’s also rng involved in that random non-targeted frenzied blast bolts may or may not be reflected by your wall, which affects the overall damage. also, these stray bolts may land just outside of the wall, causing splash damage, so you may want to give aegis to your party mates in case you’re unlucky.