Caller left message for my ex, stated they were calling for Johnson County processing division and for him to call this number to talk to law firm in charge of his account. Detailed a docket number in the message. Cannot tell if they were calling from this number, caller id only said "outside caller".

...total scam call.  Processors do NOT call to give you a heads up you'll be served.  Processors are paid to "serve" legal documents - that's it.  They don't call, nor do they contact third parties and violate the privacy of the alleged debtor by disclosing details.  These are all violations of federal debt collection law.