You could use TheTVDB to match files with episodes, and then rename files according to your episode format.
But since you just want to add something to the existing filename, it's infinitely faster to match each file to itself, and then modify the format for that.
1. Drop files
2. Hit F2
3. Double-Click any item in "New Names"
4. Change file format to your needs
The "file format" naturally only gives you access to file information. But that's all you need in this case.
Be playful. I don't think you actually need me to answer any of these questions... you could just try. It takes less time and is more fun.
Please read the manual:
viewtopic.php?f=3&t=2072