I am doubting that it is a temperature or humidity issue. Ventricosa is not picky at all as far as temps are concerned. Many, many people have success growing it in intermediate and some as a lowlander. As for humidity is concerned, I grew my ventricosa for a few years on top of my radiator in my room which was under a north facing window. Probably the worst location for a nep, but it chugged along fine. It did not pitcher for me in winter, but would come back in spring with a vengeance. My ventricosa also did not have much of a root system. My plant never produced any kind of funky leaves in it's life. Check to make sure that your peat does not contain a fertilizer. Many peat moss brands contain a fertilizer because people use it to start seedlings of plants that need it. I agree with Dex, it definitely looks like a mite attack to me. You never know where pests can come from. I had a scale attack not long ago. Came from some orchids I saved from the death rack at Lowes, which coincidentally is where I bought my sarr pots which are the same as yours. Lol. Sometimes plants just do weird things on their own as well, but immediately go back to normal. Good luck getting your plant back on track.
