One technique that has worked for some of my clients....
Fill the hole with a bunch of his own dog crap....yes that dog crap.... and then bury it....the **** needs to be near the surface....maybe a couple of inches deep at best....
Worked pretty good with my mastiff...but he wasnt an obsessed digger...just an amateur...
Coffee grounds work pretty good for cats that dig in flower beds...not sure if it would help with a dog...
The expanded metal was mostly likely used for "drainage" ----- I'd just have used any aluminum or steel plate I had laying around -- with smoothed edges... No claw damage that way.
Maybe whatever is there that is the attractant will have gone away during the next seasonal change.
That or you can put on your big boy pants and grab a shovel and dig til you find what he's looking for....
The trainer here told us when the dogs jump on the window at his office -- he just doesn't say a word - he just fry's em with the collar. Says it only takes 'em a couple times and they don't do that again. We have the type collar that you set the intensity at the control -- so it's easy to set it on fry.
Ned - being the good soul and veterinarian that he is - won't like me talking like that...
You could use one large Tucker dump -- what's that look like - a Home Depot 5 gallon bucket... ?? Oh my.... I'd be taking long walks with that dog far from anywhere I'd have to "pick up". LOL
Since I'm an internationally licensed Pyrotechnician (which really just means I have friends in the business) ----- I'd rig up a tripwire to your newly built ground pounder and set that down in the hole -- you know -- just below the surface -- and when he has his nose stuck down in the mud - and then finds that tripwire... Well let's just say - if he survives the heart attack - he won't want to revisit that hole again any time soon...
LOL
No I would never do this.... but I had nothing else to add to the subject.