I could be completely wrong.
I've just been rewatching their first vlog of this holiday where they show the hotel room/apartment thing. The one where Isla is desperate to sleep in the travel cot.
There are only four of those strawberry flower things, not five. There are only two beds in the first bedroom they show, but it doesn't look as though there's anywhere for a third bedroom to be if you watch the camera angles. It's also unlike them to not show every room, or the third of those doll things the hotel gave them. And then in the master bedroom, right before Isla starts on about sleeping in the travel cot, if you listen carefully at about 9.40, Issy says something that sounds like 'you'll have to sleep on the balcony.'
Have they got all three girls wedged in two single beds pushed together?