Gosh these plants are so confounding indeed. There appears to be no magic formula whatsoever yet...
When I first received mine it excelled in just LFS. But that changed over time. Perhaps it was that the moss grew stale and lacked some kind of nutrients after a while. I wont know for sure though because I also moved it around hoping it would prefer some other location. Now I've yet to repot it back into LFS especially after seeing Ron's plant.
In regards to the holes in your plants, I think it is funny that there has always been that belief that they need to bury their tendrils into the moss in order for them to grow. In all in situ pictures I've ever seen there is almost no moss of any kind around, and the tendrils aren't buried at all. Keep in mind this plant usually only keeps one or two pitchers at any given time in the wild.
Perhaps the entire notion of growing N. argentii anywhere other than on top of a razor sharp limestone mountain that receives gale force winds and monsoon like conditions is just new and uncharted territory for the genes of these plants.