I know nothing at all about Morgellons disease, though I think I read somewhere(in the past) that there is a conflict between Miracle-Mineral-Supplement and Silver. So you might want to check that out.
Having said that, I'm really not sure what benefits can be had from an Miracle-Mineral-Supplement enema(tbh) but I've read several reports of people claiming that Miracle-Mineral-Supplement enema's strip the mucus membrane from the colon. So you may want to be careful with that.
IMO. If it were me, and I was trying to get MMS deeper into the digestive tract or tissue, then I'd look at using DMSO as a transport method. That is to say, making a mixture of MMS/DMSO to get the MMS deeper into the body. On in this case, permeate the gut completely.
Also, have you considered trying CDS instead of MMS?
Apparently, it is less susceptible to anti-oxidation since there is no reaction involved, and its believed to work better with DMSO in terms of neutralization.
And finally, since Morgellons is most often identified as a surface condition, then perhaps a CDS/DMSO bath might work better?