Concentrations of tannic and humic acids are higher in peat, also.
The deposition of same, in the crowns (which I've noticed are common with Drosera aliciae and sometimes other varieties), can easily be remedied by a little periodic top watering, also planting the affected species in LFS (long fiber sphagnum) instead of peat based media, works.
One of the things I do to improve conditions in situations such as you describe, is to innoculate the rinsed/slightly damp peat moss with RootShield®, a brand of Trichoderma harzianum. Within a week or two prior to using it for planting. This helps control undesirable mold and fungi, though it also will eat/decompose cellulose (though, for me, with desirable side-effects). Theoretically the low pH of the peat will inhibit the Trichoderma.