My dachshund puppy's has large swollen glands in his neck.?

Please help. Has anyone experienced this problem. One of my 3 month old dachshund puppies has two large swollen lumps where his lymph glands are in his neck. I noticed it a week ago and then it was only one lump on one side. I took him the vet immediately and she said that she thought it was an abscess from a bite or sting but I couldn't see any originating wound. She sedated him and opened it up but didn't get very much liquid out. She put him on anti inflammatory tablets and antibiotics. Within four days both of the sides of his cheeks had large (about the size of a large quail egg) lumps on both sides. I rushed him back to the vet again. This time they had four vets look at him and none of them know what it is. He does not have any other swollen lymph nodes anywhere else on his body and no other symptoms and he is 99% normal in his behavior. He is one of a family of five dogs, three dachshunds and two retrievers and he is playing, eating, peeing, pooping and sleeping as usual. None of his spunk has gone and his coat and skin and temperature is normal but I just can't imagine that having two huge lumps in his throat isn't affecting him somehow. When I took him back to the vet the second time (Friday) they took a sample of one side and I won't get the results until Monday or Tuesday. However, after they took the sample I did manage to get about a tablespoon amount of liquid out of the side that they took the sample from. Since then, in the last 24 hours, I haven't been able to get anything out of it. He looks like a chipmunk storing nuts for the winter. Despite the humor, I am really worried. Has anyone come across this with their dog before or has ever seen anything like this before? I've worked at a vet clinic and I've had five dachshunds (he's a miniature) and numerous dogs over many years working with a rescue org. but I have never seen anything like it. I use a large well known veterinary clinic and four vets there also didn't know what it was. Does anyone have any idea??? I think he is sleeping a little more than usual but he is still a puppy and I have his sister who sleeps about as much as he does. I would be so appreciative if anyone has experienced this before and could give me some more information. I can't tell you how appreciative I would be.