I would be calling the docs office and have him admitted. We went through this with our granddaughter and within a few hours she was feeling better. She was in an oxygen tent with a humidifier going. She slept deeper and was out in a couple of days.
As for the snot get a snot sucker with a clear bulb on the end. You are going to have to be mean...it feels mean but in fact you are helping them get better much quicker.
I roll the kids up in a blanket to hold them down. Then I plug one nostril up a bit and put the snot sucker on the other nostril. I suction out the snot and get tons of it out. Then I switch nostrils. The plugging up the other nostril helps to get the snot that is in the back of the throat up and out too.
He needs to be in the fresh air. The germs are all over the house and reinfecting him. In the older days...a couple of hundred years ago, docs started learning about germs. They realized that getting the windows open, fresh air circulating, allowing them to go outside even, helps them get over their illness quicker. It is the best thing ever. Of course letting them get chilled or too hot is not good either.
I had pneumonia and was in the hospital when I was just 3. It is one of my very very very first memories, I remember standing in the baby bed and seeing my mom coming up the hallway. I remember getting home and my sister having to baby sit me. We went out on the porch for a few minutes and I started puking up snot. I remember thinking it was snot. I assume is was mucus and puss. I felt so much better after that. I could breathe.
I think if he is still running such a high fever and still has the excess mucus he needs to be where they can suction out his nose and throat if needed and where they can keep him in a moisture rich environment.