In most cases if a decoration was planned, the scribe coping the text would leave room on the leaf for the skilled artist to add it in later. Just like with corrections of the text where it is crammed tightly into lines, if not enough space was left a decoration looks crammed into the space. However, we cannot know if it was just a scribe forgetting to leave enough or an unplanned decoration. There are always hints such as finding a small scribal note or if the decoration doesn’t match the date of the manuscript, but it isn’t easy to know for certain.

On this leaf,  the ruling lines made by the scribe so that he didn't take up too much of the page are still visible. This is a big clue that these scenes were apart of the original intent when making this manuscript.

This image in contrast to those above is noticeable less polished.  If we look closely at the space between the three knights heads and the bottom of the text, it is easy to see that the image has been butted up right next to the text. While this is not a reason to answer definitely that this image was unplanned, it does suggest it.