I loosened the perch with the arrow pointing to it and tried spinning the threaded tube from right to left, but it won't move whatsoever.

I loosened the bolt on the bottom of the strut to try to turn it that way, but when i turn it, the entire thing rotates (top is still connected).

I sprayed wd40 and rust check lube all over it and hammered it to let the liquid go inside but still won't move. Waited 3 hours and sprayed it and hammered it again every 3 hours but no luck.

Shocks are too long right now, spring bucket is ~2cm loose which is causing the spring to bottom out and make a pop noise.

 

Sounds like the lower mount is seized up a bit. You might have to take the shock out to unstick it.

 

That's a coilover right and not a shock? I know it's a PIA but I'd remove it and shoot a little WD40 on the threads then break it loose, carefully. Can we assume you got the correct wrench to adjust the collar?
Gary

 

^He mentioned he was able to break the collar free, but he can't actually rotate the shock itself within the lower mount.