Interesting to hear about your daughter developing shingles 14 or so days after the MS diagnosis. Stress often precedes shingles by roughly the same time span.
Surely research has now established beyond doubt - viruses are a definite part of the MS equation, just as they have been saying about the peripheral nerves equivalent of MS - Guillain Barré Disease - for ages now, even though the role they play may not actually be an active one.
Herpes, Epstein Barr and HH-6 viruses may (or may not) play an active
pathalogical role in MS...they could all be bystanders, catalysts or by products - but the curious presence of the Varicella Zoster Virus DNA (and antibodies) during attacks is beyond dispute.
I think it is immensely important establishing any part of the MS equation - because the more pieces of the equation that are known, the easier it should become to work out the "active" parts.
On the other hand, the fact that candida overgrowth is known to be present in all case of aids and cancer, has never, to my knowlege solved the mystery of those diseases.
By the way, sorry to hear about your 14 year old. I'm sure you will find lots of support and information here on this site. MS has a scary reputation but isn't always so terrible. Many with the illness get off lightly and I hope she will turn out to be one of those people.
I am a great believer that learning to cope with stress and anxiety is paramount, though it's unlikely to get so much as a mention from the neurologists. Of course, this is a big ask for anyone struck down by a debiltating and unpredictable disease.