214DC can be 2D'd by Arakune to neutralize it.
Arakune can hit Lambda out of her Zwei Cavalier in any block string, he has no reason to jump, if your eyes and reaction time is legit, then Lambda is bringing herself to you for free.
Zwei Blade is the issue, it's hard to punish in a block string, and just flat out unpunishable on block for Arakune (Maybe 6C can stuff it, since it's a low, need to test).
Arakune is one of the few character who cannot be guard crushed by Lambda so easily.
That match up is indeed hard, but not for the reasons you listed. No smart Lambda will throw out parsers like that.