Hello @ericaolive and welcome to Connect ENT. We are just fellow patients with experience in various aspects of this medical specialty so hopefully you will find someone who has a history of sinusitis to throw in their 2 cents worth.
Did the doctor say these organisms are all pathogenic or are some normal flora? Was there any discussion of adding in a GI probiotic to help stabilize your normal gut microbiome? I understand that this can also support our immune system as well. You are in a tough spot with MS and needing immunosuppression to control that while also needing a healthy immune system to fight infection. Perhaps these few months off will help you to battle the sinusitis, but I imagine that is a wait and see type of proposition. You might discuss with your doctor beta Glucan as an immune augmentation. There are studies that support it as an immune system supporter. I would continue to work with both your ENT and MS doctors and if you find that you are spinning your wheels then ask for a referral elsewhere. Sometimes it is beneficial to travel to a larger facility for more specialized care. You are your own best advocate for your health care.