The problem with every weapon you named is that they are either not shock or pea shooters.
SMGs have low damage, the Vibrant pulse is great on crowds but otherwise, it’s damage is lacking.
And shields resist Cryo. Not only on damage but on freeze chance too. You are only dealing 40% damage instead of 250%… On Deadlift, forget about it. Cryo is for mobs. (Maybe a few bosses, but DL is not among them)
Get Snipers or Shotguns in shock and a shock Longbow grenade: Deadlift is 90% shield.
Maybe even a shock RL. If you like company man, a shock Hyperion shotgun would be a great fit.
As for your shield. Shock immune will only protect you against DoT, not all shock attacks. Since DL mainly deals shock damage (and you take 2.5x damage on your shield from them) your best bet is an Adaptive shield: not only will you take less damage from shock while your shield is up, but you’ll only take x1 damage on your health for longer before dying.