It seems MRSA is everywhere. My adult daughter struggles with it too. I've researched quite a bit, and the scientific evidence of Essential Oils effectiveness is on the rise, but there's so much involved. My daughter (dd508) has been hesitant to try EOs on her MRSA, for fear of interactions with her current treatments. I can't blame her, because EOs are potent, and there's most likely some hype and misinformation out there online.
That said, I personally witnessed my father, who has/had MAC, benefit greatly from EOs defused in his home. His case was not as complicated, but he went from not wanting to leave home due to constant coughing and breathing difficulties, to having his active life back. EOs have soothed his lungs without the hefty antibiotics that had disrupted his whole digestive tract. I truly believe EOs (and herbs) are worth looking into, but definitely do your homework and don't believe everything big companies claim, especially where safe usage is concerned. A site I like is Hopewelloils.com (formerly Heritage Oils), which has a lot of educational information and posts their sources.
In Oregon and Washington state there are also a couple of naturopathic institutes that train MDs to be NDs, so they learn the chemical science of EOs and herbs, and how they interact with conventional treatment. That seems to be where the treatment of these super bugs will need to go. Praying you find some good answers for your son.