Neither ampullaria or ventricosa are going to experience low temperatures commonly in the wild, and though hybrids tend to be more tolerant it probably won't want temps below 70 either.; most Nepenthes might be cool highland plants but even most of their habitats still at least get to the 70's regularly during the day With ampullaria as a parent this is one cross that might do okay with sitting in a tray (most Nepenthes do NOT like wet feet, and should be kept just moist in an aerated soil mix, though plants in household humidity will tolerate the trays better than greenhouse plants), and with ventricosa it will tolerate lower humidity, but moderate moisture and high humidity are both going to be wants for it to do best, and daytime temps in the upper 70's to low 80's F at least, with a fair drop at night, and humidity of at least 50%, preferably higher.
In the photos the crisping leaf edges typically are due to some sort of unwanted extreme (can be frost, sunburn or water burn, extremely low humidity that cause similar looks), and if it's sitting by a radiator then it's definitely going to be a combo of sudden humidity drops and heat increase that it's currently hating. On a windowsill it might also be experiencing temp swings as the sun comes up and goes down too.