In order to properly tension the belt you are now going to need to take the hydraulic damper back out and compress it in a vice and put the stop back in. Then you reinstall the damper.
To tension the belt you use the tensioner pin wrench as shown in the picture and rotate it counterclockwise until you can remove the stop. Go clockwise with the wrench until you can stick a 5/16" drill bit in as shown and torque the 13 mm nut to 25 NM. Then rotate the engine around twice and check the gap between the stop on the tensioner and the tensioner. It should be from 6 to 10 mm.