I've done my fair share of editing, as well, and I'm in the same boat as you. It can get confusing and not be sure what to do. Company names change over time, especially when they've been around for 30/40 years. Everyone calls Konami, Konami, which would of worked back in the late 80's. However, they're called Konami Digital Entertainment Co., Ltd. now. Another thing is divisions or subsidiaries. When you say Rockstar, do you mean Rockstar Games the publisher or Rockstar North the developer? So, whenever I'm editing, I use the full name (Co., Inc., whatever included). This way there is absolutely no confusion. But, that's just my preference.
As far as remasters, I'd just use the developer that actually made the remaster. Even though they are not the people that made the original game, they ARE the ones that made the one you're talking about. Plus, the developer of the original game had nothing to do with the remaster.
Last, but not least, the arm of the publisher. This would follow the same guideline as what I said first. If it's SCEA Europe, then I'd put the Europe at the end.
But, what do I know? Like I said earlier, this is just my preference, sooo...yeah.