Umm, yes. If he has legal control over the website and domain he can cut it loose and doesn't need to support it until after a petition and order is filed requiring him to maintain the property. He might get scolded but I highly doubt her counsel will want to pony up money to hire an acturial to determine the value of the website, lol.
Thinking that lawyers being involved cools things down, shows lack of experiences.
I highly doubt he has any legal control. Most likely he just has the username and password to the hosting company and said fuck it, I'll shut it down and "show her".
It won't cool anything down, but seriously, her attorney will make a case that her primary source of income and the company which is in her name was illegally shut down. They could even press it as a cyber crime if they so desire.
This simply shows a lack of foresight on PJs part, and to be quite honest, a desire to be a dick.
I've been through divorce court myself and I've been able to argue numerous things on my behalf and have them go in the proper way... Divorce court proceedings are not like criminal courts and "feelings" do count to judges in those proceedings.
The right judge and the right argument and PJ will be fucked.