Wow, you're doing really well with N. argentii!
I haven't noticed N. vogelii requiring anything in particular. It's been one of my easier plants for a while and just receives the usual highland to intermediate swings throughout the year. Pretty tough species that's probably similar in cultivation requirements to N. stenophylla, N. fusca, or maybe N. faizaliana.
That N. flava is awesome! What is inside the N. eymae pitcher?
Mato, how many N. rajah u have? That N. rajah pitcher looks to be sitting on top of N. rajah forest lol
Good luck with those N. campanulata, Mat. Hopefully you can get at least a little pollen while the female is still receptive.