So I have some good news and bad news...
Good news:
-dyndolod doesn't take hours anymore its more like 5-10 minutes again since i turned a lot of stuff down and used billboards instead
-I think i found out why those whiterun stable trees dont render from far away:
explanation- The tree mod causing the issue is this mod https://www.nexusmods.com/skyrimspecialedition/mods/16230?tab=description "whiterun trees overhaul", turns out when i checked the download file it literally only includes a esp file and not any textures,billboard or lod files. I checked its requirements and found out that "Skyrim 3D trees and plants" was a optional file to work alongside it, but I already have a another skyrim tree model replacer mod - "Veydogolt Trees" and it includes its own billboard and lod files for generation which actually works ingame for other trees outside whiterun but for some reason it doesn't work for the "whiterun trees overhaul". "Skyrim 3D trees and plants" also has its own files needed for lod and texgen so i can assume this is why those trees are not showing up at all, which makes sense now. Veydogolt Trees has its own whiterun tree addition mod - https://www.nexusmods.com/skyrimspecialedition/mods/63251 which i will be trying next to see if anything changes with the render distance.
Bad news:
-Tree still doesn't render from far(i will be changing tree mods for the reason stated above so this issue in not that problematic anymore)
-Whiterun walls seem to be flickering in and out of 2 textures or something see video for reference: https://imgur.com/a/xvJkyhW
I'll be back to report my testing to see if the other whiterun tree mod has the same issue. Thanks for the help so far i really appreciate it.