Basically, as long as both authors have deliberated over the action between each of their characters, it's not god-modding. Drawing up a situation concerning the actions of both characters is the easiest and most effective way of interaction as long as there is agreement between both parties.
So really, it's not god-modding.
I never said it was god-modding. I explicitly identified it as a "loophole". There is no rule against it, it's just something I tend to discourage. When a character performs an action, ideally it should be that characters' RPer who describes that action. You may discuss the allowance of another RPer to control your character, but may find that RPer doesn't describe your character's actions particularly the way you would have preferred. Also, when there is a group of characters together in one scene, it can get confusing and hectic for one RPer to be controlling the actions of multiple characters, whether it was discussed beforehand or not.
I suppose it really boils down to personal preference tbh. Personally, I wouldn't want the actions or dialogue of my character primarily portrayed through another writer's style, regardless of how creative or skilled they were. They can use my own descriptions to reiterate my characters' actions in their own post, but never directly control it. Maybe I'm just anal about it, but it really depends on the RPer.
It's my RP and if I've discussed something with another player and are taking it in a certain direction, then its not Godmodding.
Of course it's not, in fact what you just stated there is indeed encouraged, so I'm not sure why you're trying to defend something that I have no argument against. My point is there are multiple methods to go about progressing a planned plot between RPers, you have yours, I have mine. I merely offered my opinion and advice on the matter, I never said anything you did was god-modding or not disallowed in any way.
No different than previous Dessie confrontation between Fiona and Thetis.
Actually, there is a very plain difference. During the confrontation between Thetis and Fiona, Bex did not directly control the conscious actions of Fiona; and when Fiona became virtually incapacitated, there were no actions from her to be controlled, only Thetis' actions unto her. L2differentiate.
Also as a courtesy to the other RPers, it would be nice to at least make mention that you are planning a scene between your own character and another so as to keep everyone generally in the loop. As the game mod, you should help eliminate any possible confusion that may arise.