There was a case relayed, where a man was going through domestic violence but could not leave the situation because he is undocumented and needs her to get his immigration status changed. Help may be difficult for him to find. Shelters for men, and services may seem non-existent or hard to find. I've heard women in similar situations of domestic violence and immigration status whose cases got special consideration due to domestic violence. This org might have some info about that:
https://www.chirla.org/who-we-are/connect/contact-us/
The ones i heard more specifically about are:
https://saharacares.org/legal-services/
and
https://www.southasiannetwork.org/awaz
I also heard that for immigration cases like these, a police report of a crime is required.
For a man in this situation, it's important to understand that this also includes codependency and a good book on the topic is:
"Codependent no more"
by Melody Beattie
Getting help a support group for men, could be very beneficial. He might be helped by this resource for men:
http://www.menscenterlosangeles.com/welcomehome
I know a man who got general support here, while he was going through a divorce. From a men's group:
https://mankindproject.org/mens-groups/
"A Gathering of Men"
https://www.youtube.com/watch?v=TP3HWLIL1Aw
"Iron John"
https://promisekeepers.org/