I recommend using Magic TXD instead. https://www.gtagarage.com/mods/show.php?id=27862
TXD Workshop is prone to errors and may corrupt data.
Guide for creating TXD
Game exporters usually ignore custom rotation/scale values and reset them back to 0 on export. Try applying your custom transforms/scale in object-level and it'll show up in the correct scale
As this question is mostly a server/scripting support question, it's been moved into a better place for best result .
We are not able to help with unlocking/decrypting server assets here - you would have to use a backup key to do this yourself.