When Inheriting Tenants- Need a new lease?

[D.J. Paris III]

We purchased a building in Jan with a bad tenant in Chicago, IL.
The previous landlord had a simple 2 page lease without information about security deposit, etc..

Now that tenant is suing us for not disclosing where we kept the security deposit funds among other items of missing paperwork found in ordinary leases. The fee is 2x security deposit plus attorney fees

The question is, do they have an argument if the lease they have is signed by the old owner and not by us?