He sounds vile. And edging towards cruel in his efforts to impose his will on his baby. Nice. Hope he's proud of himself.
Has he not learnt the basics of being a parent yet?
You give unconditional love, you don't demand it back in whatever form you've decided it must be displayed. She's 2 yrs old ffs.
It's our job to help their children feel secure and confident enough to thrive in different situations.
It's our job to help them learn to cope with their emotions and a world which can seem exciting and scary.
It's our job to manage their fears until they can manage their fears themselves.
It's not a parents job to deliberately put them in situations where they are overwhelmed by bad feelings and watch them suffer...
Basically he's teaching her the wrong message, because he's not actually thinking about his little girl, it's all about himself.
She's going through a clingy phase which is completely typical. It happens and it passes. She's realising that the world is big and actually, mummy being with her makes it fun, as she's completely secure and feels safe as she knows you'll always protect and reassure her when she needs it.
And yet, instead of thinking, oh ok, its normal, and I can help my toddler through this phase by making sure she feels as safe with me, her daddy, so the clinginess will pass quicker'... Noooo, he's thinking that he wants her to feel differently so he's going to break her in, to force her to feel secure by punishing her, forcing her away from her mummy, and deliberately not preparing, explaining, reassuring and distracting, no why would he do that? He refuses to reassure her that mummy will be back, he just is angry, then gives up and leaves her completely alone, and generally storming around like a stroppy toddler.
That is not the way to build a bond with his child. It's also not the way to help her learn to feel secure. Or to help her understand it's ok for mummy to go, as she'll always come back.
He's doing a great job at showing his dd that she's far better being with her mummy, and that she cannot rely on her daddy. Way to go there champ (idiot).
Problem is, will he listen to you or have any insight into his own behavior and how he is making the clinginess worse? Some people don't want to learn and develop skills, they just want to act like a dick.