866-701-0042

This number called my mom who lives out of state and claimed to be Scott County (MN) courts saying that I needed to contact them immediately or a warrant would be issued for me.

I live in Scott County, I called the district court and they have no record of me at all.

called asking for elderly mother claiming to be process server for local county suspect scam

Scam.  Called for my elderly father (who was just scammed out of a lot of money) said that they are process servers.  I called them back and advised every number they call me from I'm forwarding to the FBI.  She said "FBI isn't talking to you" I said "wanna bet?".

She would be correct in that this is not something the FBI would get involved in unless it went through the regulatory agencies first and then went to the DOJ.  You should be filing complaints with the CFPB and your State Attorney General.

Called for my ex-husband (from 15+ years ago) claiming to need to speak with him urgently from "process service dispatch" in St. Louis County regarding some kind of complaint.

Scam! Real process servers don't call in advance.

I got a message in my voice mail without receiving a phone call.  They left a callback number of 866-701-0042.  A female caller claiming to be jacklen says "this is a urgent message intended for (My daughter's name)".  From (unintelligible) dispatch saying she is calling about a "notice of action of complaint"  She left a "case number" and said that failing to contact them will result in further proceedings without her consent.
I told my daughter about it but neither one of us is going to call this woman back, it is obviously some kind of scam.