Thanks for your interest and help then!

Well, renaming can be an iterative process IMHO and since conventions change, I believe it is better to have it renamed and saved, even if the names need to be further polished in the future. Still that does not means to just dump a truckload of new files and hope someone renames them later

I think you can start with your initial idea, leave the original pdfs with their names and rename the zip (known here as the "setfile") with the proper TNC name. After that you will end with a folder full of zips (and pdfs inside), which belong all to the same Collection and create a datfile. That might be a good first renaming exercise and give you a datfile ready to submit. After that and if you feel like it would be better / be better organized to also rename the pdfs go for it.
As for the IDG vs IDG Entertainment, we don't have a 100% fixed rule or way to enforce that (at the moment). We try to minimize the usage of different "names" for the same groups, publishers and so on and also avoid enormous filenames. That being said, you can try to stick with what has been used before, if and only if, it makes sense and is the exact same company. If you think it would be more correct to use IDG Entertainment (because it changed to that over time, is the most known name or whatever) you can use it too. Just make sure you are at least coherent in the same dat/collections and stick with the same choices.
Anything more we can help, just ask!