Please review the Q&A Usage Guidelines, specifically point 3, "Quote the applicable rule from the latest version of the manual in your question." Often, you'll find that by quoting the rule, you'll answer your own question!
The definition of Scored states the following regarding a Ball inside of a Cube:
a. A Ball is Scored inside of a Cube if it meets the following criteria:
i. The Ball is at least partially within the three-dimensional volume defined by the outer edges of the Cube’s structure.
ii. The Ball is not contacting the Floor “outside” of the Cube. The portion of the Floor which is “outside” of the Cube is roughly defined as a vertical projection of the Cube onto the Floor beneath the Cube, regardless of the Cube’s orientation.
In order to be Scored inside of a Cube, both of these criteria must be met. You are correct that the second criteria is being met due to the vertical projection of the Cube.
However, based on the photo you have provided, it appears that the first criteria is not being met. The Ball is not at least partially with the three-dimensional volume of the Cube.
Therefore, this Ball would not be considered Scored.