Ansen can keep absorbing energy around herself. She has telepathy and telekinesis so she can also just keep summoning snakes from her being to shield herself. She has fought someone who used a similar sealing-like attack and survived it.
Dura Neg is required to destroy the Dragon Egg because it is beyond her physical being, more specifically within her stomach. He has to actually destroy the egg itself which he won't be able to do. He would need stupidly high physical strength to crush it. Telekinesis will not work as you need to physically (not telekinetically) crush it with your hand. More snakes will keep appearing and she'll keep returning.
She is in Third Release, her stats will all keep increasing constantly and she'll keep healing.
Even if they can't do anything to Mob, they can keep firing venomous water from a distance. She can summon an earthen wall to repeatedly shield herself from any of mob's telekinetic attacks.
Ryudo 7's range isn't clear but if it has already hit him once (which it already would've at the beginning of the fight), it will keep on landing, no matter where he is, even in flight. Mob can't toss the attack away as its effect will be to hit him. Several characters have tried tossing the attack away or used forcefields but it never worked because the attack will ALWAYS land and negate his durability, causing him to be damaged. And she will spam it after getting crushed once. She also has ESP and enhanced senses so she should be able to see or sense him no matter where he is. She can then point her fingers at his location and then he gets Gojo'd.