Interestingly, I found a similar problem today with Verbatim 8x DVD+R (MCC003) in 100 disc cakebox.
The cakebox had a white paper marketing disk inside the cakebox on top, and several soft white spacer rings.
I've found white stuff on the disks, and the top disc has a white clump that would not come off without enough pressure to put faint scratches in the surface.
I've also found lots of dust in shrink-wrapped TY ValueLine disks.
However, Taiyo Yuden cakeboxes have no paper disk, no rings, and no dust of any sort.