Ahhellitshim

So For the mod i am creating i have ran into a weird road block?

Ok so because of the mod i am creating i am trying to find out what is the program that rdr2 uses for 3D models and can i port 3D models from other games and 3D modeling soft wear like sketch fab and blender?

I recently found this program OpenIV which is apparently a way to get into the get into the game files.And mess about with them. But I have also heard that you can't really edit them is this true?

Because i had a conversation with a Moderator that said yes to not being able to edit them at first but then he told me that it would be things that people have all ready learned? 

So i am just trying to get the closest to a clear answer. And if it is a yes i would like the program link or just how to do it. Then i found this web site https://zenhax.com/viewtopic.php?t=12388 "a few other links https://gtaforums.com/topic/933869-wipr, And The Zenhax link has a conversation about some one who has found a way to mess with the game files. And i quote said this 

"BX .OBJ exporter.. This is Rage Engine. Its not easy with encryption. Use the program to export textures and models as .FULL files. Open with Model Researcher find your offsets and export to .OBJ." end quote So what i think of all of this. To truly open the game files OpenIV is needed but another program which is unknown and people treat it like gold or bigfoot. So why is this not all available and not a INSANITY QUEST to find?