Looks like you may be right. Lucy's back, and the warden is still on her prison ship.
She and Johnny did have another getting-to-know you scene, though. As the series winds to an end, I can still see the warden joining Johnny as the team breaks up.
Johnny, the warden and Lucy 2.0 will be a threesome. Dutch and D'Avin will live happily ever after.
At the rate Daddy D'avin's and Mama Delle's "kid" is growing, he'll be a middle-aged man by the time the series ends -- ready to rebel, move out of his parents' basement and strike out on his own. No relationship complications for Dutch and D'avin.
The Warden will, of course, turn command of her prison ship over to the inmates to join Johnny and Lucy on their new adventures. I'm confident that the two ladies will soon work out their very different relationships with Johnny and become a cheery threesome.