We know for sure that it works. I forced the Charlie Plinth into the CM:TP ending cinematic. It just sat there in the background like some weird easter egg. Very cool. I demonstrated this to Enigma in-game.
For any planned hijinx, you want to know the lay of the land. Let's look at CM:TP district progression:
D06 > D08 > D05.
In other words, you begin in D06. You enter D08. You then enter D05. The mission when you open Dare's pod.
If the campaign loading process works the same way in CM:TP as it does in CM:MS, what will happen is that any objects you brings from D06 into D08 will despawn when you hit the D05 preload boundary.
This is bad news, because the dead elite bodies are in D06.
For this endeavor, I suggest we belay the theorizing about whether the game engine continues to process enemy movements, etc and just go do it to find out! You can play this mission on Easy and never kill a single enemy. I takes all of 2 minutes, I think.
Here are two tips based on my experience:
DO NOT seek the treasure!
(whoops) what I meant was DO NOT go into D05 until you have your objects assembled and ready to go over the line into D05. When you're ready, inch those suckers just over the district boundary without going too far into D05. Why? Because that DD between D08 and D05 permanently closes on you if you walk too far into D05. You don't want the objects you just kicked across two districts to be locked behind you, do you?
Block the scene. This is a theater/film term which- in this context- equates to figuring out exactly where in Dare's crash site your objects should be placed so that they appear where you want them when the cinematic runs. You may think you have the perfect place to put your plinth, only to find out that the cinematic camera's perspective causes another object to completely obscure the view of it. This is what Enigma has been explaining in his posts. Basically you want to first become familiar with the cinematic without trying to alter it. Take note of which shots are the longest and try to get your object into that shot. Make your first attempts with something easy to move and repeat the process until you have it in the right area. Once you have found the right area, take note of where exactly on the floor it was placed so that you can always do it again later.
I look forward to the crazy movies we'll be watching once the SGP Film Project gets rolling!