How so? The Philica/Chloe scene is entirely consensual, certainly more so than the Maat scene in Eternum. If you go ahead with that scene, Chloe has already consented to it, you (as a proxy of MC) have consented to it, and Philica has of course consented to it, since it's her idea in the first place. The fact that Philica's confused about MC's relationship with Chloe is irrelevant (though as with MC/Grace, I think Philica's seeing more than MC and Chloe are willing to admit about their relationship). MC doesn't get off, but again, that's what he's agreed to, and that's at least part of why Philica's paying MC (the other part being whatever the female version of cuckolding is). In this scene, everyone gets exactly what they agreed to.
I don't really see the Maat scene as a parallel. Yes, she's (apparently) more sexually-experienced than that MC, but I think that's where the parallel ends--she's forcing MC and Nova into that scene at gunpoint (Nova's gun, no less). They aren't risking actual death, but that still makes their consent at least questionable. When (if) that MC has sex with Maat, that's entirely consensual, but what gets them there is at best semi-consensual.