ok I will ty to explain this high resolution DLC idea I talked about before.
since you guys have prepared those pcc files and your way is to simply replace the pcc files with same names in the vanilla \\Mass Effect 3\\BIOGame\\CookedPCConsole
why not making a sfar file like this? using Javik's DLC as an example

Using 7zip to pack the pcc files that contain high resolution textures. if successful, the game will load the high resolution DLC and the textures inside. but there is this problem:

I don't know how to edit this file. with notepad, I guess this bin is a list of files in the dlc's cookedpcconsole
if this DLC method works, it will be much easier to install. we don't have to worry about damaging / losing original files in ME3's vanilla cookedpcconsole folder.
Ciao.