I only own a young miranda but the difference i would think is the hybrid, do you have pics of both plants?

N. Miranda Hybrid is:
Nepenthes maxima x (maxima x northiana).

The N. Velvet hybrid is:
N. fusca x maxima

Sorry this is separate had to leave for a little while so i couldn't look up the hybrids, hope this helps, both plants do look similar

Thank you very much, I was puzzled till you came along,

Always,
Ken