Did KP have surgery around the time of the incident? I'm sure someone mentioned that on one of the other threads (they move fast lol). Would this be a left over bruising from that?
So there's a row, then there could have been him pushing past her, she fell. Him shoving her away from him if she might of tried to hug him (insisting it's all nothing, don't be silly type thing), or the phone was thrown and caught her?
May not necessarily have been a punch, beating, stamp, kick, etc., but more an injury due to it being a stumble or knock in a very small floor area (coffee table/chairs kid's toys) and a mark has appeared, due to knocking into any of those, particularly if KP was intoxicated.
Equally, the make up may have been to "enhance" the apparent injury for the camera?
I've known people to lie in A&E, full on blatantly lie, either to cover up something so they don't get in trouble, or anyone else, or equally, play out a scenario to assure that another person is blamed and held accountable, even if they weren't actually
Those who live for drama, love to create it and revel in viewing the carnage they set up. Bit like those who set dynamite to erase an old building, still hang around in their hard hats watching the buildings crumble and watching the dust settle