Amending I140 & company divestiture

Hello

My company has 2 subsidiaries (Sub A and Sub B). They filed my PERM with petitioner as Sub A but I used to work in Sub B which got sold to another company which assumed everything of Sub B as successor in interest.
As a result I moved to that new company along with the role. Nothing changed for me except the company name.

I had an I-140 approved with that old company’s Sub A. Can I use the I-140 from Sub A as petitioner to file I485 or new employer needs to file a new PERM and I140?

New employers attorney says that they need to file a new PERM and I140 as the Sub A was not sold and only Sub B was sold as successor of interest.

Sub B needs to file new PERM and i140 for themselves.