Your probably gonna get swamped with responses to this and they are all going to vary.
This is what we did... it took me a while to finally get it right and to keep it gone.
First off, if yeast is presenting externally then there is an internal issue, I would get her on probiotics. When I got DD on probiotics it helped a lot! We may not of even had another yeast outbreak... if we did, it was only 1.
I put distilled water in a spray bottle and added about 15 drops of GSE (grapefruit seed extract) to it. I would spray her rashy area at every change and let air dry. GSE helps kill yeast. I also made her a wipe solution with vinegar, GSE, TTO (Tea tree oil) and lavender. The vinegar and TTO kills yeast. Sometimes I would add calendula as it sooths and heals skin. Also, naked booty time- lots of it... yeast loves warm and moist. In addition to all that, I would add some vinegar to her bath (at the end) to let her sit in it to help kill the yeast, for about 5 min or so. I also like Weilda Calendula Diaper care... don't know if it helped to get rid of the yeast but it helped keep her booty looking healthy.
Diaper care... I have only dealt with prefold and covers... never had yeast in wool. For my prefolds I would do my cold rinse. Then a HOT wash and a HOT rinse. I would use my regular detergent then add 45-50 drops of GSE, some vinegar and a lot of TTO. I would also add the vinegar to the rinse cycle. Then I would dry on super hot for a minimum of 2 cycles... high heat kills yeast. Make sure to not to forget any diapers so you don't recontaminate, wash all wet bags, wipes and pails. I continued this routine until the the yeast had been completely gone for a week.
I don't know about lotrumn, I never had to use it. Good luck, yeast is a total pain!