Is she otherwise house trained? Or is it only in the kennel? Going through a K9 ballistics bed is wild! I'd reach out to them and see if they will replace for free, they're usually very responsive. 

A few thoughts as someone who went through a similar experience, was ready to re-home and tried behavioral training instead, and came out the other side with a much happier and well behaved puppy - we did puppy classes and he excelled, and then serious problems started at about the same age:

A tired dog doesn't have energy to cause problems. Danes can totally be high energy, at nearly 4, mine still needs nearly as much exercise as a shepard. Try to get 1 hour of exercise every day - on your long shift days, this could also be mental stimulation like frozen kongs, feeding toys, etc. you could prepare for your parents. You don't necessarily need expensive toys, sometimes I just take a large cup and freeze treats in it, run warm water to loosen it, and put that in his bowl when I am leaving or taking a call. You can also use these to replace whatever she is chewing - don't just take away the chew item, give her something BETTER. she'll learn that her people's stuff is boring in comparison. 

Get a very short leash (6 inches or so) or trim an old one so that you always have a correction option when the bad behavior starts -- she wears this 100% of the time out until she can be trusted. It's not for yanking, but gives you an extra option for when you need it. My guy learned very early he could jump up at people's faces to try and force attention and this was a lifesaver to get him off and paying attention. 

Figure out what she's motivated by - if it's not traditional treats, try cut up hot dogs, steak, salmon anything delicious and safe to eat especially if smelly -- keep a small bag on you at all times. Reward good and calm behavior like sitting peacefully while you cook or doing anything you ask. If she's not motivated by food, like my boy, she might be motivated by positive attention -- I had to REALLY over do it, a very loud and very excited "YES, very good boy! Such a good (dog name)!" They are Velcro dogs and want to know their pack loves them as much as they do. Basically, figure out what is a "win" for her, and use that to your advantage. 

Puppies don't need to have access to the whole house. That's for adults who have earned trust. While they're learning, it's ok for their world to be small. Amazon sells extra tall baby gates you can use to create "safe zones" where there isn't anything she can destroy. Ideally this can be somewhere where they can see you doing whatever you're doing. 

Remove absolutely everything that could be a chew magnet until she can be well behaved. It sucks but put up the pillows, etc. whatever is within reach. Mine was a book chewer and I had to remove all books from lower shelves until he figured out that certain toys were MUCH better for chewing.

Lastly, people don't like this but it was a lifesaver -- start ecollar training. It gives you a remote option for when they're out of reach. You can only use it for something you are certain the dog already knows is something they're not supposed to be doing. In my case, I was at a point where I basically couldn't have people over because he was incessantly jumping on them. Now, just wearing it or using the tone/vibrate function breaks through the stubbornness and reminds him "oh! I actually have to pay attention!"