So after some testing, I realize that the sub-lumber family (Silversap, etc) will instantly break a Shield on Elite no matter what, even an Omega Shell with Freeze Maximum broke against a Silversap, this seems a bit... weird.
The attack will still inflict the same statuses without the Shield up, however, when the Shield up, it'd go from this:
*Normal Damage
*Elemental Damage
*Stun
*Secondary Status (Fire, Freeze, Shock, Poison)
to this:
*Normal Damage
*Elemental Damage
*Secondary Status (Fire, Freeze, Shock, Poison)
A minor change, but this will allow Shields with a Status Resistance to take one-full hit with about 5% - 20% of the Shield's Health remaining.
I get the impression that lumbers are just intended to be so powerful that you can't shield against them and have to rely on dodging. A lot of games with shielding mechanics and large enemies act like this.
Silversaps are really punishing in this regard, but it's possible to be immune to both of their statuses.