When I Googled "Janome binder attachment quilts", the binder attachment in the Youtube video came up right away. When I Googled the same thing but replaced Janome with Pfaff, nothing even remotely similar came up.
My bet is that this is a new attachment for Janome and the other brands have not caught up with it yet. It is different from the usual binding attachment for sewing, in that the quilting attachment feeds the binding strip in from the right. That ribbon-like feed on the right side of the attachment is really different from regular binding attachments.