A committee of the landlords, including care home operators Four Seasons and Bondcare, property investor NHP, and led by accountant Grant Thornton, has hired City agency Brunswick.
Some 80 landlords met in London on Monday to put together their own proposals to continue the operation of the care homes.
The landlords plan to take back more than half of Southern Cross' 750 homes, with Four Seasons and Bondcare running their own homes, while tenants are sought for the others. The plan could also involve a restructured Southern Cross continuing to manage a portion of the homes.
News of Brunswick's appointment comes after PRWeek revealed private equity giant Blackstone had called in Finsbury on a project basis to support media relations.
Blackstone, the former Southern Cross owner, has been heavily criticised for its sale-and-leaseback strategy blamed for dragging the firm close to bankruptcy.
Southern Cross, which provides care for about 31,000 elderly people in the UK, last month announced it was to cut a third from its rental bill.