I researched this a bit and I believe that the export via PDF from Tabcmd with the scroll bars is not possible currrently. Check out this Idea - https://community.tableau.com/ideas/8002 and vote for it please if it meets your need.
Thanks, Patrick. I voted for it.
For the time being, I figured the solution out:
$tabcmd export $URL --pdf --width 1700 --height 2300 --pagelayout portrait -f $FileName
Here we set the width and height of the PDF file to accommodate all the columns and then we change the dashboard resolution on the server to match the width and height of the pdf as well. Then we can print the data without the scroll bars as everything is shown on the dashboard in the server.
Hope it helps somebody.