Hm. Interesting idea. Doesn't really make sense that the wife would believe some random over the (supposed) father of her children but that could be explained.
They have to stay up in the Tower in order to redo the sky barrier. The whole intention behind this attack was to force the mages down so that the barrier wouldn't be properly activated and whatever lies beyond could come through.
Ho ho ho, Will is simply too damn cool. I hope this manga gets made into an anime, Wistoria deserves one more than all of the generic isekais that have been adapted recently. All of the chapters up until now would make an exceptional first season.