I didn't write the patch so I don't know how it works. I don't use the patch, either. I did download that patch after seeing your first post, extracted the /src folder as explained by the person who wrote the patch, and the game started with no problem.
However, simply changing the name of the characters to something different shouldn't keep the game from starting with the patch in it. If the patch was written properly, it would just skip translating lines if it can't find what it is looking for, leaving the original lines. You could and ask them.
You could test your assumption by making sure the game is exited, deleting the /src folder, start the game, rename them back to Debbie and Jenny, exit the game, extract the /src folder into the /game folder of the Summertime Saga directory, and try to start the game to see if it works.