Have you tried filling a regular Kong with a mix of his kibble + some peanut butter or apple sauce or something similar and freezing it? This would last a lot longer than the Kong Wobbler as your pup will have to work hard to get the food to melt and come out. If you're worried about him chewing up the Kong, there is also the Kong Extreme version which is more durable.
Another good option is this Goughnuts ring, which is guaranteed indestructible (they also have a tug toy). I would certainly take the guarantee with a grain of salt, but the ring may be a good option for when he's bored.
Additionally, you can look into puzzle toys like these:
Outward Hound Star Spinner Interactive Doy Toy Puzzle for Dogs
TRIXIE Dog Activity Flip Board
Ethical Pet Seek-A-Treat Shuffle Bone Dog Puzzle
They are great for giving your pup a small job to complete to get a reward. Also, since your dog destroys things sometimes you'll want to use your judgement about what is safe to leave him alone with.
At the end of the day the best way to ensure your pup isn't destroying all of your furniture and belongings is to make it more rewarding to practice another behavior or to remove the reward from this behavior. It will be a bit easier to remove the reward than to compete with it, so that's what I'll focus on. Your dog sounds pretty bored if he's chewing up the couch while you're away - especially given that when he's well exercised at daycare he doesn't act out like this for a day or so after. Daycare is expensive, but you're going to pay one way or another. Right now you're paying in the destruction of your stuff. With daycare you pay with your money. Another option is to pay is in time. Spend more time exercising your dog - take him to the park every morning (even 30 minutes of running around with other dogs might be enough to get him through the day).
I'm also assuming you've gone through basic obedience training when you first got your dog. If not, start there. Your pup should be reliable with basic commands, such as sit, stay, and come (that last one is a life saver). Aside from daily trips to the dog park or dog daycare (assuming this is your only dog), you can practice obedience training throughout each day as this will expend a lot of your dogs mental energy. If you can afford to, getting your dog into a sport (like agility or flyball) will alleviate a lot of his excess energy which he's currently releasing onto your couch. You can search for a training club near you here.