As much as I'd like to believe they'd take the Girls to Florida, i really bleeping doubt they will, partly because the idea of Nick spending out money on someone else's plane ticket wouldn't be something he'd offer, let alone for 2 kids. Secondly, they had no intention of picking up anything remotely caring for the girls while they were there last time, which highlights just how little he thinks of them.
No most likely, they'll read this, and make an impromptu booking for Disneyland Paris, as they can all drive over that way for an all in one price of the ferry using the Pricks Savilemobile while getting Janine to book another car over (or coaxing a parent to drive). They'll do a stay at Davy Crocketts being the cheapest place on the site, so they can try out the camper, but also having a 3 bed lodge and then lord it over the kids for about 2-3 days, before sending them packing, as they duck off further into Europe.
The sheer idea of them spending more money for additional days with the nieces is something they'll never entertain, no, better have the kids in a couple of vlogs to help sell the next adventure, then off to greater Europe for Pizza and Curries..