There is a difference sometimes between guaranteed base purse and overall take home pay, some fighters can opt for a higher guarantee, instead of base pay + instead of smaller slice of PPV,.
https://en.wikipedia.org/wiki/Sergey_Kovalev_vs._Andre_Ward
https://en.wikipedia.org/wiki/Andre_Ward_vs._Sergey_Kovalev_II
shows elements of this flexibility
The rematch wasn't immediate, (which is why I put the word immediate in bold twice, in my previous post)
If it's not immediate, that means a rematch clause likely hasn't been triggered, so it's a new round of negotiation, largely from scratch.
Bottomline
There is little reason for whyte to be a b side in a rematch after having beaten AJ, an even less reason for wilder, seeing as Hearn admits Wilder is a bigger name in the US
Well the Ward vs Kovalev example is useless as only Wards final purse is announced in those links, so the A side was who exactly.
No that isn’t the bottom line it’s your opinion and nothing more and it’s an opinion which can be comfortably disputed.