Stag and Vixen dynamic is different yes. The reason why I didn't mention it is because in most case when I dealt with Vixen, it was them having the fetish. Which in this case, a completely different dynamic where the male is a "cuck" but has the control because it's the wife (vixen) that wants to sleep with other men. This is where the other post make sense where the MC dictates what the wife can and what she can't do. I dealt with very controlling husbands with the wives not having any option as a say because in a snap of a finger the game ends.
Cuckcold play and stag/vixen play is such a volatile thread because it based on trust + the significant other willing to continue. That's why the power always gets transferred to the one who doesn't have the fetish and only doing it for their significant other.
In VR, Amie isn't a stag yet, she's only sleeping with other men because the MC wants it. For Amie, she has the power to end this power dynamic because she didn't actively chose to sleep with other men until MC revealed his fetish.