Where can I find the tdpdk 13.11 and 13.12 and where can I find the installation instructions for the required viewpoint.
Have you considered asking in the Viewpoint Forum?
Generally speaking, your Teradata CSR should be able to acquire the software and perform the upgrades for you.
However, if you are asking about TD Express then you'll definitely want to hit the Viewpoint Forum and see if one of the gents from the Viewpoint team can point you in the right direction. I'm not aware of how updates to TD Express are handled.
The Viewpoint Exchange is a great resource. Here is the link to the configuration guide.
The latest Viewpoint PDK is version 13.03 and can be found within the Viewpoint channel. An updated release of the PDK is needed. Working on that with Teradata R&D.