He means the icons you see before you actually enter the match e.g. on Hangar Hats Off! in game there is a flattering picture of a Henchman, but on the wiki there's just a random emulater screenshot using an FoV modifier.
I disagree on the 'Jacque reanimated the Priests' part, as the TS2 bios it says '''''The Undead Priests are all that remains of Jacque'''s cult followers. Under his influence they sacrificed their souls for immortality''' meaning that the agreed to immortality at a time that Jacque could either persuade or possesse them, and they also don't act like normal zombies in TS2.
I blame all of this weird mess (Strange possible relations and killing the same person multiple times) on wibbly wobbly timey wimey stuff caused by the Splitters. We've seen the same person in one timeline before in FP, haven't we? And by the way 'Out of town' is used to describe Tony's brother in the briefing could be the same logic as in the Dock Duck Shoot 'Out of town' alien competitors, meaning he could be Mister Big brought from a very distant place, e.g. another timeline.
Cortez does occasionally take damage and grunt in a sometimes Female / Robotic voice, plus in the Siberia cutscene Ilsa / Cortez does speak in her voice, so the doppelganger retains it's vocal cords and therefore the same voice.
Well, since we know that the Undead Priests are immortal (Likely caused by the Time Splitters) and were long enough for their ENTIRE skin layers to decompose (They shouldn't have been too old at the time that they became immortal) and that the Colonel and them are only 32 years apart, I chose to believe that they had met earlier. The aztecs, well. Maybe they weren't the aztecs, and they were actually one of those civilisations that 'randomly dissapeared without a trace' before them. Maybe the Time Splitters have something to do with the Temple's 'Lost' status.