Ill take your word for it, as you probably have more intimate knowledge than I. However, it would be relatively simplistic for them to have in the contract "you get X percent of ppv and X base" and thats it, versus something that fluctuates based on the opponent and the amount of advanced notice he gets before the fight. For instance, when a fighter like Al takes a fight on short notice, you would think that there is a huge inscentive (a kicker) that Al got. Maybe Nate was angling for that discretionary amount.
Or maybe he was chicken......
A UFC fighter has to sign for X-amount per fight & contractually UFC has to offer them x-amounts of fights per year (varies from 1-3)
If not they UFC has to pay the the show money or contract is voided
Of course a fighter can say no & many do
If a fighter says no, then the UFC is off the hook for that fight
So IF UFC offered Nate a Khabib fight around the time of RDA, it would have been per the amount he agreed to in his contract.
Nate could have said no for a myriad of reasons. I don't think "scared" was one .
Basically the UFC cannot legally offer any UFC fighter less than what the contract stated that both parties agreed to when they signed a deal for X-Amount of fights at X-dollars
they can offer more obviously as an incentive.
but that usually comes with some bargaining power (fighter on a win streak, last minute notice, main event, etc)
Around that time, Nate famously re-signed with UFC for shit pay per fight because UFC paid a huge signing bonus upfront (he owed taxes).
So I bet he said no in hopes of more money, but UFC had to offer fights to him at whatever they agreed to.
I think that makes sense