A: judgments are only enforceable against defendants who have been served with the Summons and Complaint. if all parties are not served, then only those served can have an enforceable judgment entered against them.
A: a signed contract, and that is what a lease is, is an agreement between two parties. if one party to the lease makes unilateral changes that have not been agreed by the other party, then those changes are not a part of the agreement the parties have. they other party's agreement is manifested by their signature to the new contract or initials to any written additions.
A: if there is no written lease, then your tenant has a month to month tenancy. you can give them a 30 days notice. if they have not moved by the end of the 30 days, then you can file an eviction action.