Script Save As with stamps increases file size

Hi all,

I currently have a working script that saves the PDF to a fixed location depending on the user input.

Everything seems to work, however, if the user adds some digital stamps to the PDF before running the script, the file size increases (the stamps are less than 1mb, but the file becomes > 10mb) and each time they run the script, it will increase the file size two folds (Double)

Is there any way to fix this or is there a way to run the optimize PDF or a regular "save as" that doesn't save the overhead from scripting?