Your plant certainly appears to have become the meal for some errant Lepidopteran larval invader. Even here in the desert southwest, I've sometimes discovered Lepidopteran larvae munching on various CP. Sometimes they can almost completely devastate a solitary plant, before their presence is discovered. Then, locating and eliminating them is an even more complicated/difficult chore. I do try not to use many complex man made chemical pesticides. And even using Bt would be tedious and overkill, against the incidental and occasional Lepidopteran invader.
The key is to be vigilant and familiar with their handiwork, so as to identify their presence as soon as possible, then to develop a technique to locate them and remove them, expeditiously, while causing the least collateral damage to the plant(s).
Your Pinguicula grandiflora, is a very handsome specimen. I wish you all the luck with saving it from the monster(s) that are eating it.
sflynn's submersion plan sounds viable - I've used it with success.