What is a DAP infuser? Do the drugs work at all?
Not having a dog, I am hardly qualified to comment, but I will anyway

If you're not seeing any change with the meds (you didn't say), I'd take him off them. Get some Rescue Remedy from the health food store and put a good 20-30 drops in his water bowl. It is completely non-toxic. Repeat every time you provide fresh water.
I'd let him sleep where he wants at this point. Poor guy.
You might want to consult an animal behaviourist. I hear some of them are pretty good.
Is he getting lots of exercise?
It's a big change for you, so it has to be huge for him. Is the puppy OK?