As the video above shows, since the text is on layers above the footage - it does not overlap with the objects like they should (such the poles on the sign post). To fix this, I crated a mask and animated it so it'd cover up the parts of the text that should go behind objects. This was a bit fiddly at times, since the mask was also parented to the null object, but it wasn't too difficult to sort out. Another problem is when the the camera moves from the front of the sign post to the back, the text is mirrored on the opposite side. To fix this, I animated the appropriate scale attribute to -100 to flip the text into the correct orientation. I did this when the text was flat so the change could not be seen.
I also noticed that sometimes you get better results depending on which edges you use to place the locators in Maya. For some sign posts, I got better results when I selected an edge from the front, and one edge from the back of the sign. Other sign posts I had better luck with selecting two edges next to each other. I just continued to experiment until I got the results that I wanted.
I am still finding the font 'Noteworthy' the most useful so far for replacing text that does not agree with 'Grenouille'. I used the font 'Bradley Hand' for Bulgarian in this test.