Dude, don't even get me started on the RNG topic: it LOOOVES to mess me up!
Was once farming Fishron for its wings on a ranger playthrough, farmed all the Terrarian day and night: Flairons,Bubble guns,friggin Razorblade Typhoons a plenty and NOT EVEN ONE PAIR, and if that wasn't enough the game threw a Blood Moon during the farming just to make my life even more miserable.
Bottom line is: just keep going and think that you're making tons of money as a consequence of they not dropping the thing.
It HAS to drop at some point