From the ESPN article:
"The conference would also be subjected to $43 million in poaching fees, as outlined in the scheduling agreement between the conferences this year that resulted in Oregon State and Washington State playing six Mountain West opponents.

IIRC, the scheduling agreement said that they either had to invite ALL of the MWC teams to join or if they only wanted some of the MWC teams, they had to pay the 'poaching fee' for every individual team that they invited. So WSU & OSU will end up paying $3.6 MILLION per game for the MWC to fill out their schedules for this 2024 season.

I can understand that OSU & WSU were desperate for games after their former conference mates abandoned them, but that's a lot of cash to pay for the privilege of playing games in Reno, Albuquerque, Fresno, etc. this year.