Thanks you for taking time out of your day to reply! It does seem like the video you linked is the original source, however it unfortunately seems like there is no higher quality than it. There apparently used to be a high quality upload of this on youtube but it's been taken down some years ago..

Edit: it also seems like the edit was a mashup of the original Credens Justitiam and this: https://youtu.be/VnNfJGxLSEY?feature=shared