Hi Alison
It’s hard to advise, without knowing what sort of dogs, are they left unsupervised in the back garden, etc. If the dogs are the type who are likely to leave the hogs alone, are well trained (i.e. could be told/trained to leave the hogs alone) and are supervised when they are in the garden, I would be inclined to say make as much garden wildlife friendly as possible. But there may be some dogs where I would think differently. Don’t forget to encourage all your neighbours to make accessways for the hogs as well. The more gardens the hogs have access to, the less likely they will need to cross roads to find suitable habitat.
Hedges sound brilliant to make the front garden more hog friendly. If you dig a hole under the chain link fence the hogs will probably find their way under it, but you might want to make it look neater (and less likely anything can get caught on the fence). I’m not much in to woodwork, myself, but image you could make some sort of wooden structure, if you couldn’t get a suitable pipe. I imagine the best place to get a piece of pipe would be either a builders merchant, or possibly even a scrap/reclamation yard.
You may already have seen these, but, more tips for making gardens more wildlife friendly here:
https://www.hedgehogstreet.org/help-hedgehogs/helpful-garden-features/
and hog holes:
https://www.hedgehogstreet.org/help-hedgehogs/link-your-garden/