Sorry to hear the hogs have all gone missing.
Hogs sometimes won’t stay in areas where there are badgers. Badgers are probably their main natural predator. But it’s also coming up to hibernation time. Some hogs – males in particular – may have already started hibernating. But they may also be slightly changing their habits and spending more time in the vicinity of their chosen hibernation sites. Bearing in mind that normally male hogs can travel up to 2 miles a night – their Summer ranges must be fairly large.
For instance I have a hedgehog here who built a nest in one of my hog boxes (actually previously used for feeding!). Whilst he isn’t actually hibernating yet, he is spending far more time in the area around his nest, and in my garden generally, than he would normally do at other times of the year. Normally he would have been visiting from elsewhere. So the owners of the other gardens he normally visits, may well be wondering where he is.
So don’t worry too much. As long as the badgers haven’t actually moved into the area permanently, which might be a problem, hopefully hogs will return in the Spring. This is always a worrying time of the year, but fingers crossed for all the hogs everywhere. Good luck.