The male rats weren't really parthenogenetic.
Rather, they were acting as "nannies" for the baby rats, tending them in small groups and periodically carrying them to the females for milk. That's why the baby rats were too well-developed to be newborns: the captive male didn't actually give birth inside the bag, another male'd just happened to stash some babies inside it when Jackson wasn't looking. The leopard won't be usable for a cure anymore, sending the team back to the drawing board.
The fisherman who rescued Jamie and the leopard cub had no way of knowing that it needed to be kept free of Mother Cell contamination, so would have no reason not to feed it Reiden-made kibble or meat from contaminated animals. This is a prequel to Wayward Pines.
Humans mutating into Abbie-like monstrosities could hint that they end up dominating the world in a few hundred years.