Try a search for “417 militia.” I saw no hits from that except for hits from the same news story about the two criminals (emphasis on “story”) and from some street addresses that include the phrase.
The media people made it up, or the tipster made it up. They should know better. So should the feds, if they reported that part of the story without checking it out first.
“417” has been used to refer to methamphetamine made in the Ozarks, though. It’s the area code in that area. And who likes meth? Commie rioters...and maybe the Ozark crooks arrested in Kenosha.
The claim about a militia looks like it came from a commie swamp.
There was ONE page on a bulletin board with 4 posts on it. https://www.mymilitia.com/profile/2951-417-2nd-amendment-militia/